Disorders implicating pufa oxidation

ABSTRACT

Some aspects of the invention provide for a method of treating hepatic disorders, lipidemias and cardiac-related risk factors using polyunsaturated fatty acids which are modified in certain positions to attenuate oxidative damage by Reactive Oxygen Species (ROS) and/or suppress the rate of formation of reactive products and toxic compounds.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to U.S. Provisional Application No. 61/479,306, filed Apr. 26, 2011 and U.S. Provisional Application No. 61/479,311, filed Apr. 26, 2011; which are hereby expressly incorporated by reference in their entirety.

BACKGROUND Field

Isotopically modified polyunsaturated fatty acids (“PUFAs”) and other modified PUFAs for treating certain diseases, particularly hepatic disorders, lipidemias and cardiac-related risk factors.

Description of the Related Art

Oxidative damage is implicated in a wide variety of diseases such as mitochondrial diseases, neurodegenerative diseases, neurodegenerative muscle diseases, retinal diseases, energy processing disorders, kidney diseases, hepatic diseases, lipidemias, cardiac diseases, inflammation, and genetic disorders. Specifically, such diseases include but are not limited to fatty liver diseases, including alcoholic and non-alcoholic varieties, steatohepatitis, cirrhosis, and hepatocellular carcinoma.

While the number of diseases associated with oxidative stress are numerous and diverse, it is well established that oxidative stress is caused by disturbances to the normal redox state within cells. An imbalance between routine production and detoxification of reactive oxygen species (“ROS”) such as peroxides and free radicals can result in oxidative damage to cellular structures and machinery. Under normal conditions, a potentially important source of ROSs in aerobic organisms is the leakage of activated oxygen from mitochondria during normal oxidative respiration. Additionally, it is known that macrophages and enzymatic reactions also contribute to the generation of ROSs within cells. Because cells and their internal organelles are lipid membrane-bound, ROSs can readily contact membrane constituents and cause lipid oxidation. Ultimately, such oxidative damage can be relayed to other biomolecules within the cell, such as DNA and proteins, through direct and indirect contact with activated oxygen, oxidized membrane constituents, or other oxidized cellular components. Thus, one can readily envision how oxidative damage may propagate throughout a cell give the mobility of internal constituents and the interconnectedness of cellular pathways.

Lipid-forming fatty acids are well-known as one of the major components of living cells. As such, they participate in numerous metabolic pathways, and play an important role in a variety of pathologies. Polyunsaturated Fatty Acids (“PUFAs”) are an important sub-class of fatty acids. An essential nutrient is a food component that directly, or via conversion, serves an essential biological function and which is not produced endogenously or in large enough amounts to cover the requirements. For homeothermic animals, the two rigorously essential PUFAs are linoleic (cis,cis-9,12-Octadecadienoic acid; (9Z,12Z)-9,12-Octadecadienoic acid; “LA”; 18:2; n-6) and alpha-linolenic (cis,cis,cis-9,12,15-Octadecatrienoic acid; (9Z,12,15Z)-9,12,15-Octadecatrienoic acid; “ALA”; 18:3; n-3) acids, formerly known as vitamin F (Cunnane S C. Progress in Lipid Research 2003; 42:544-568). LA, by further enzymatic desaturation and elongation, is converted into higher n-6 PUFAs such as arachidonic (AA; 20:4; n-6) acid; whereas ALA gives rise to a higher n-3 series, including, but not limited to, eicosapentaenoic acid (EPA; 20:5; n-3) and docosahexaenoic (DHA; 22:6; n-3) acid (Goyens P L. et al. Am. J. Clin. Nutr. 2006; 84:44-53). Because of the essential nature of certain PUFAs or PUFA precursors, there are many known instances of their deficiency and these are often linked to medical conditions. Furthermore, many PUFA supplements are available over-the-counter, with proven efficiency against certain ailments (See, for example, U.S. Pat. Nos. 7,271,315 and 7,381,558).

PUFAs endow mitochondrial membranes with appropriate fluidity necessary for optimal oxidative phosphorylation performance. PUFAs also play an important role in initiation and propagation of the oxidative stress. PUFAs react with ROS through a chain reaction that amplifies an original event (Sun M, Salomon R G, J. Am. Chem. Soc. 2004; 126:5699-5708). However, non-enzymatic formation of high levels of lipid hydroperoxides is known to result in several detrimental changes. Indeed, Coenzyme Q10 has been linked to increased PUFA toxicity via PUFA peroxidation and the toxicity of the resulting products (Do T Q et al, PNAS USA 1996; 93:7534-7539). Such oxidized products negatively affect the fluidity and permeability of their membranes; they lead to oxidation of membrane proteins; and they can be converted into a large number of highly reactive carbonyl compounds. The latter include reactive species such as acrolein, malonic dialdehyde, glyoxal, methylglyoxal, etc. (Negre-Salvayre A, et al. Brit. J. Pharmacol. 2008; 153:6-20). But the most prominent products of PUFA oxidation are alpha, beta-unsaturated aldehydes such as 4-hydroxynon-2-enal (4-HNE; formed from n-6 PUFAs like LA or AA), 4-hydroxyhex-2-enal (4-HHE; formed from n-3 PUFAs like ALA or DHA), and corresponding ketoaldehydes (Esterfbauer H, et al. Free Rad. Biol. Med. 1991; 11:81-128; Long E K, Picklo M J. Free Rad. Biol. Med. 2010; 49:1-8). These reactive carbonyls cross-link (bio)molecules through Michael addition or Schiff base formation pathways, and have been implicated in a large number of pathological processes (such as those introduced above), age-related and oxidative stress-related conditions, and aging. Importantly, in some cases, PUFAs appear to oxidize at specific sites because methylene groups of 1,4-diene systems (the bis-allylic position) are substantially less stable to ROS, and to enzymes such as cyclogenases and lipoxygenases, than allylic methylenes.

We have now discovered that oxidation resistant PUFAs, PUFA mimetics, PUFA pro-drugs and/or fats containing oxidation resistant PUFAs and PUFA mimetics are useful for mitigating hepatic disorders.

SUMMARY

Some embodiments provide a method of treating or inhibiting the progression of a hepatic disorder, comprising administering an effective amount of a polyunsaturated substance to a patient having alcoholic fatty liver disease, non-alcoholic fatty liver disease, steatohepatitis, cirrhosis, hepatocellular carcinoma, obstructive jaundice, cholelitiasis, or a biliary tract disease and in need of treatment, wherein the polyunsaturated substance is chemically modified such that one or more bonds are stabilized against oxidation, wherein the polyunsaturated substance or a polyunsaturated metabolite thereof comprising said one or more stabilized bonds is incorporated into the patient's body following administration. Other embodiments provide a method of treating or inhibiting the progression of lipidemias or cardiac-related risk factors, comprising administering an effective amount of a polyunsaturated substance to a patient having lipidemia, liporegulation disorders, lipotoxicity, ischemic heart disease, hypertension, atrial fibrillation, left ventricular hypertrophy, coronary artery disease, or atherosclerosis and in need of treatment, wherein the polyunsaturated substance is chemically modified such that one or more bonds are stabilized against oxidation, wherein the polyunsaturated substance or a polyunsaturated metabolite thereof comprising said one or more stabilized bonds is incorporated into the patient's body following administration.

In some embodiments, the polyunsaturated substance is a nutrition element. In other embodiments, the nutrition element is a fatty acid, a fatty acid mimetic, and/or a fatty acid pro-drug. In other embodiments, the nutrition element is a triglyceride, a diglyceride, and/or a monoglyceride comprising a fatty acid, a fatty acid mimetic, and/or a fatty acid pro-drug. In some embodiments, the fatty acid, fatty acid mimetic, or fatty acid pro-drug is stabilized at one or more bis-allylic positions. In other embodiments, the stabilization comprises at least one ¹³C atom or at least one deuterium atom at a bis-allylic position. In some embodiments, the stabilization comprises at least two deuterium atoms at one or more bis-allylic position. In other embodiments, the stabilization utilizes an amount of isotopes that is above the naturally-occurring abundance level. In some embodiments, the stabilization utilizes an amount of isotopes that is significantly above the naturally-occurring abundance level of the isotope.

In some embodiments, the fatty acid, fatty acid mimetic, or fatty acid pro-drug has an isotopic purity of from about 20%-99%. In other embodiments, the isotopically stabilized fatty acids, fatty acid mimetics, or fatty acid pro-drugs are administered to a patient along with non-stabilized fatty acids, fatty acid mimetics, or fatty acid pro-drugs. In some embodiments, the isotopically stabilized fatty acids, fatty acid mimetics, or fatty acid pro-drugs comprise between about 1% and 100%, between about 5% and 75%, between about 10% and 30%, or about 20% or more of the total amount of fatty acids, fatty acid mimetics, or fatty acid pro-drugs administered to the patient. In some embodiments, the patient ingests the fatty acid, fatty acid mimetic, or fatty acid pro-drug. In some embodiments, a cell or tissue of the patient maintains a sufficient concentration of the fatty acid, fatty acid mimetic, fatty acid pro-drug, triglyceride, diglyceride, and/or monoglyceride to prevent autooxidation of the naturally occurring polyunsaturated fatty acid, mimetic, or ester pro-drug. In some embodiments, the stabilization utilizes an amount of isotope that is significantly above the naturally-occurring abundance level of said isotope.

In some embodiments, the method utilizes a fatty acid, fatty acid mimetic, or fatty acid pro-drug that is an omega-3 fatty acid and/or an omega-6 fatty acid. In other embodiments, the fatty acid selected from the group consisting of 11,11-D2-linolenic acid, 14,14-D2-linolenic acid, 11,11,14,14-D4-linolenic acid, 11,11-D2-linoleic acid, 14,14-D2-linoleic acid, 11,11,14,14-D4-linoleic acid, 11-D-linolenic acid, 14-D-linolenic acid, 11,14-D2-linolenic acid, 11-D-linoleic acid, 14-D-linoleic acid, and 11,14-D2-linoleic acid. In other embodiments, the fatty acids are further stabilized at a pro-bis-allylic position. In some embodiments, the fatty acid is alpha linolenic acid, linoleic acid, gamma linolenic acid, dihomo gamma linolenic acid, arachidonic acid, and/or docosatetraenoic acid. In some embodiments, the fatty acid is incorporated into the mitochondrial membrane. In other embodiments, the fatty acid pro-drug is an ester. In some embodiments, the ester is a triglyceride, diglyceride, or monoglyceride.

Some embodiments further comprise co-administering an antioxidant. In some embodiments, the antioxidant is Coenzyme Q, idebenone, mitoquinone, or mitoquinol. In other embodiments, the antioxidant is a mitochondrially-targeted antioxidant. In some embodiments, the antioxidant is a vitamin, vitamin mimetic, or vitamin pro-drug. In other embodiments, the antioxidant is a vitamin E, vitamin E mimetic, vitamin E pro-drug, vitamin C, vitamin C mimetic, and/or vitamin C pro-drug.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B. (1A) ROS-driven oxidation of PUFAs; (1B) formation of toxic carbonyl compounds.

FIGS. 2A and 2B. ¹H- and ¹³C-NMR analysis of deuterated PUFAs described in Examples 1-4.

FIG. 3 . Sensitivity of coq null mutants to treatment with linolenic acid is abrogated by isotope-reinforcement. Yeast coq3, coq7 and coq9 null mutants were prepared in the W303 yeast genetic background (WT). Yeast strains were grown in YPD medium (1% Bacto-yeast extract, 2% Bacto-peptone, 2% dextrose) and harvested while in log phase growth (OD_(600 nm)=0.1-1.0). Cells were washed twice with sterile water and resuspended in phosphate buffer (0.10 M sodium phosphate, pH 6.2, 0.2% dextrose) to an OD_(600 nm)=0.2. Samples were removed and 1:5 serial dilutions starting at 0.20 OD/ml were plated on YPD plate medium, to provide a zero time untreated control (shown in top left panel). The designated fatty acids were added to 200 μM final concentration to 20 ml of yeast in phosphate buffer. At 2 h, 4 h, and 16 h samples were removed, 1:5 serial dilutions prepared, and spotted onto YPD plate medium. Pictures were taken after 2 days of growth at 30° C. This panel is representative of two independent assays, performed on different days.

FIG. 4 . Yeast coq mutants treated with isotope-reinforced D4-linolenic acid are resistant to PUFA-mediated cell killing. The fatty acid sensitive assay was performed as described in FIG. 3 , except that 100 μl aliquots were removed at 1, 2, and 4 h and, following dilution, spread onto YPD plates. Pictures were taken after 2 to 2.5 days, and the number of colonies counted. Yeast strains include Wild type (circles), atp2 (triangles), or coq3 (squares); Fatty acid treatments include oleic C18:1 (solid line), linolenic, C18:3, n-3 (dashed line) or 11,11,14,14-D4-linolenic, C18:3, n-3, (dotted line).

FIG. 5 . Separation and detection of fatty acid methyl ester (FAME) standards by GC-MS. FAMEs were prepared as described (Moss C W, Lambert M A, Merwin W H. Appl. Microbiol. 1974; 1, 80-85), and the indicated amounts of free fatty acids and 200 ag of C17:0 (an internal standard) were subjected to methylation and extraction. Samples analyses were performed on an Agilent 6890-6975 GC-MS with a DB-wax column (0.25 mm×30 m×0.25-m film thickness) (Agilent, catalog 122-7031).

FIG. 6 . Uptake of exogenously supplied fatty acids by yeast. WT (W303) yeast were harvested at log phase and incubated in the presence of 200 μM of the designated fatty acid for either 0 or 4 h. Yeast cells were harvested, washed twice with sterile water and then subjected to alkaline methanolysis and saponification, and lipid extraction as described (Moss C W, Lambert M A, Merwin W H. Appl. Microbiol. 1974; 1, 80-85; (Shaw, 1953 Shaw, W. H. C.; Jefferies, J. P. Determination of ergosterol in yeast. Anal Chem 25:1130; 1953). Each designated fatty acid is given as μg per OD₆₀₀n, yeast, and was corrected for the recovery of the C17:0 internal standard.

FIG. 7 . Kinetics of O₂ consumption accompanied the oxidation of 0.71 M LA (plots 1 and 2) and 0.71 M D2-LA (plot 3) in chlorobenzene initiated by 40 mM AMVN at 37° C. Plot 2-0.23 mM HPMC was added to 0.71 M LA.

FIG. 8 . Dependence of the rate of oxidation of the mixture of LA and D2-LA in chlorobenzene solution on mixture composition. Conditions: [LA]+[11,11-d₂-LA]=0.775 M; [AMVN]=0.0217 M; 37° C. R_(IN)=(1.10±0.08)×10⁻⁷ M/sec.

FIG. 9 . Isotope reinforcement at the bis-allylic position of polyunsaturated fatty acids attenuates lipid autoxidation. Wild-type, yeast Q-less coq3, or respiratory deficient cor1 null mutants were incubated in the presence of 200 μM of LA and D2-LA at different ratios of PUFAs. Serial dilutions (1:5) starting at 0.2 OD/ml were spotted on YPD solid plate medium. A zero-time untreated control is shown on the top left. Growth at 30° C.

FIG. 10 . Isotope reinforcement at the bis-allylic position of polyunsaturated fatty acids attenuates lipid autoxidation. Wild-type, yeast Q-less coq3, or respiratory deficient cor1 null mutants were incubated in the presence of 200 μM of ALA and D4-LA at different ratios of PUFAs. Serial dilutions (1:5) starting at 0.2 OD/ml were spotted on YPD solid plate medium. Growth at 30° C.

FIG. 11 . Chromatograms of the yeast extracts subjected to GC-MS analyses. The different traces represent the 0 and 4 h incubations, respectively. The peak area of Each FAME (C18:1, C18:3 and D4-linolenic) was divided by the peak area of the C17:0 standard, quantified with a calibration curve. The endogenous 16:0 and 16:1 changes very little, while the exogenously added fatty acids increased significantly.

FIG. 12 . Survival of H- and D-PUFA treated MVEC cells after acute intoxication by paraquat. For all cell types tested, D-PUFA had protective effects compared to controls, similar to that shown for MVEC cells.

FIG. 13 . Animal dosage studies of 1:1 D2-LA/D4-ALA indicating tissue enrichment with deuterium.

FIG. 14 . Animal dosage studies of 1:1 D2-LA/D4-ALA comparing any changes in fat distribution.

FIG. 15 . Animal dosage studies of 1:1 D2-LA/ALA indicating tissue enrichment with deuterium.

FIG. 16 . Control liver fat profile after 90-day animal dosage study.

FIG. 17 . Animal dosage studies of 1:1 D2-LA/D4-ALA indicating liver fat profile and enrichment with deuterium.

FIG. 18 . Liver fat profile after 90-day animal dosage study with D2-LA.

FIG. 19 . Animal dosage studies of 1:1 D2-LA/D4-ALA indicating brain fat profile and enrichment with deuterium.

FIG. 20 . Animal dosage studies of 1:1 D2-LA/ALA indicating brain fat profile and enrichment with deuterium.

FIG. 21 . Control brain fat profile after 90-day animal dosage study.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As used herein, abbreviations are defined as follows:

-   -   αLnn Alpha-linolenic acid     -   4-HUE or HHE 4-Hydroxyhex-2-enal     -   4-HNE or NHE 4-Hydroxynon-2-enal     -   AA Arachidonic acid     -   ACE Angiotensin-converting enzyme     -   AFLD Alcoholic fatty liver disease     -   ALA Alpha-linolenic acid     -   AMVN 2,2′-Azobis(2,4-dimethylvaleronitrile)     -   CAD Coronary artery disease     -   CHF Chronic Heart Failure     -   D Deuterated     -   D1 Mono-deuterated     -   D2 Di-deuterated     -   D2-LA Di-deuterated linoleic acid     -   D3 Tri-deuterated     -   D4 Tetra-deuterated     -   D5 Penta-deuterated     -   D6 Hexa-deuterated     -   DHA Docosahexaenoic (22:6; n-3) acid     -   EPA Eicosapentaenoic (20:5; n-3) acid     -   dL Deciliter     -   DMF Dimethylformamide     -   EtOH Ethanol     -   FAME Fatty acid methyl ester     -   FLD Fatty liver disease     -   FRAP Ferric reducing ability of plasma     -   HPMC 6-Hydroxy-2,2,5,7,8-pentamethylbenzochroman     -   H-PUFA Non-deuterated polyunsaturated fatty acid     -   IP Intraperitoneal     -   IR Infrared     -   KIE Kinetic isotope effect     -   LA Linoleic acid     -   LDL Low-density lipoprotein     -   LVH Left ventricular hypertrophy     -   MDA Malondialdehyde     -   mg Milligram     -   MI Myocardial infarction     -   MPTP 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine     -   MVEC Microvascular endothelial cell     -   NAFLD Nonalcoholic fatty liver disease     -   NASH Nonalcoholic steatohepatitis     -   PPAR Peroxisome proliferator activated receptor     -   PQ Paraquat     -   PUFA(s) Polyunsaturated fatty acid(s)     -   R_(IN) Rate of initiation     -   ROS Reactive oxygen species     -   R_(OX) Rate of oxidation     -   RPE Retinal pigment epithelium     -   SNOMED Systematized Nomenclature of Medicine     -   SOD Superoxide dismutase     -   TDMS Toxicology Data Management System     -   TH Tyrosine hydroxylase     -   THF Tetrahydrofuran     -   TLC Thin layer chromatography     -   V-SMOW Vienna standard mean ocean water     -   WT Wild type     -   YPD Medium containing 1% Bacto-yeast extract, 2%     -   Bacto-peptone, 2% dextrose

Hepatic Disorders Implicating PUFAs

Abnormal lipid metabolism plays an important role in the pathogenesis of many liver disorders. Fatty liver disease (FLD), whether it is alcoholic (AFLD) or nonalcoholic (NAFLD) consists of hepatic steatosis (fatty liver) and steatohepatitis (progressive inflammation, or hepatitis, of the liver). FLD often progresses toward the development of cirrhosis and hepatocellular carcinoma. The indistinguishable spectrum of histological features of both AFLD and NAFLD suggests a convergence of pathogenetic mechanisms that enables the progression of steatohepatitis toward cirrhosis and liver cancer. Excess energy consumption and reduced energy combustion appear to be critical events that culminate in excessive lipid storage in the liver. Energy combustion in the liver is controlled by peroxisome proliferator-activated receptor (PPAR)-regulated mitochondrial and peroxisomal fatty acid oxidation systems and the microsomal oxidation system. PPAR, a receptor for peroxisome proliferators, functions as a sensor for fatty acids (lipid sensor), and ineffective PPAR-sensing can lead to reduced energy burning resulting in hepatic steatosis and steatohepatitis. (Reddy J K et al, Am J Physiol Gastrointest Liver Physiol 2006; 290:G852-858).

PUFA processing is diminished in obese NAFLD patients, in association with underlying insulin resistance and oxidative stress, which leads to altered lipid metabolism favoring fatty infiltration (Araya J et al, Obesity 2010; 18:1460-1463). Excess saturated fatty acids are known to inhibit the activity of desaturases. This leads to an elevated ratio of peroxidation-prone linoleic and linolenic acids (Puri P et al, Hepatology 2007; 46:1081-1090).

Accumulation of lipids within hepatocytes initiates the development of non-alcoholic steatohepatitis (NASH). The primary metabolic abnormality leading to lipid accumulation (steatosis) may result from insulin resistance and alterations in the uptake, synthesis, degradation or secretory pathways of hepatic lipid metabolism. The steatotic liver may then be vulnerable to further injury when challenged by additional insults. The progression from simple, uncomplicated steatosis to steatohepatitis to advanced fibrosis results from two factors, the first (mainly insulin resistance) leading to accumulation of fat within hepatocytes, and the second (mostly reactive oxygen species) leading to lipid peroxidation, cytokine production and Fas ligand induction. Oxidative stress and lipid peroxidation are key factors in the development and progression from steatosis to more advanced stages of liver damage (Angulo P. et al J. Gastroent. Hepat. 2002; 17:S186-190).

Increased oxidative stress in accumulated fat is an important pathogenic mechanism of liver disorders and metabolic syndrome in general (Furukawa S et al, J Clin Invest 2004; 114:1752-1761). Imbalance of PUFA ratios, in combination with increased oxidative stress characteristic of hepatic disorders, leads to elevated levels of reactive carbonyl compounds such as MDA, HNE and HHE (Poli G. British Med. Bull. 1993; 49:604-620). These are known to be involved in numerous detrimental pathways, including, but not limited to, irreversibly damaging cellular components, activating apoptosis, etc.

Oxidative stress is implicated in the pathogenesis of NAFLD. Measurement of hepatic and plasma oxidative stress-related parameters suggests that liver protein carbonyl content is enhanced by more than 4-fold in patients with steatosis, whereas glutathione content, SOD activity and the ferric reducing ability of plasma (FRAP) are substantially decreased. Oxidative stress was found to develop in the liver of NAFLD patients with steatosis and is exacerbated further in patients with steatohepatitis. Substantial protein oxidation is followed by proteolysis of the modified proteins, which may explain the co-existence of a diminished antioxidant capacity and protein oxidation in the liver of patients with steatohepatitis (Videla L A et al, Clinical Sci 2004; 106:261-268).

Patients with chronic hepatitis, obstructive jaundice, cholelithiasis and related conditions also have increased levels of hepatic lipid peroxides, while plasma levels of oxidised lipids were found to be not different between patient and control groups (Tsai L Y et al, Clinica Chimica Acta 1993; 215:41-50).

Biliary tract diseases are also characterised by increased oxidative stress and lipid peroxidation (Feher J et al, Scandinavian J Gastroenter. 1998; 228:38-46).

Some aspects of this invention arise from: (1) an understanding that while essential PUFAs are vital for proper functioning of lipid membranes, and in particular of the mitochondrial membranes, their inherent drawback, i.e., the propensity to be oxidized by ROS with detrimental outcome, is implicated in hepatic disorders such as alcoholic fatty liver disease, non-alcoholic fatty liver disease, steatohepatitis, cirrhosis, hepatocellular carcinoma, obstructive jaundice, cholelitiasis, and biliary tract diseases; (2) antioxidants cannot prevent PUFA peroxidation due to stochastic nature of the process and the stability of PUFA peroxidation products (reactive carbonyls) to antioxidant treatment, and (3) the ROS-driven damage of oxidation-prone sites within PUFAs may be overcome by using an approach that makes them less amenable to such oxidations, without compromising any of their beneficial physical properties. Some aspects of this invention describe the use of the isotope effect to achieve this, only at sites in essential PUFAs and PUFA precursors that matter most for oxidation, while other aspects contemplate other sites in addition to those that matter most for oxidation.

Isotopically labeled embodiments should have minimal or non-existent effects on important biological processes. For example, the natural abundance of isotopes present in biological substrates implies that low levels of isotopically labeled compounds should have negligible effects on biological processes. Additionally, hydrogen atoms are incorporated into biological substrates from water, and is it known that the consumption of D₂O, or heavy water, does not pose a health threat to humans. See, e.g., “Physiological effect of heavy water.” Elements and isotopes:formation, transformation, distribution. Dordrecht: Kluwer Acad. Publ. (2003) pp. 111-112 (indicating that a 70 kg person might drink 4.8 liters of heavy water without serious consequences). Moreover, many isotopically labeled compounds are approved by the U.S. Food & Drug Administration for diagnostic and treatment purposes.

It will be appreciated by those skilful in the art that the same effect can be achieved by protecting oxidation-prone positions within PUFAs using other chemical approaches. Certain PUFA mimetics, while possessing structural similarity with natural PUFAs, will nevertheless be stable to ROS-driven oxidation due to structural reinforcement.

Lipidemias and Cardiac Related Risks

Oxidative stress occurs from an imbalance between the production of ROS and endogenous antioxidant defense mechanisms. Interestingly, oxidative stress and abnormal lipid metabolism play an important role in the pathogenesis of many lipidemias and heart disorders.

Lipidemias (lipemias; hyperlipidemias; hypolimidemias) are conditions manifested by abnormal levels of plasma lipoproteins and cholesterol, caused by primary (genetic, such as Tangier and fish eye diseases) or secondary (such as smoking) factors. Low levels of high-density lipoprotein (HDL), or hypoalphalipoproteinemia (HA), include a variety of conditions in which concentrations of lipoproteins or HDL are reduced. Indeed, the American Heart Association's guidelines for fasting HDL cholesterol levels and risk for heart disease indicates that men with less than 40 mg/dL (less than 50 mg/dL for women) of HDL are at heightened risk for heart disease, whereas 40-59 mg/dL is considered a medium level of HDL and greater than 60 mg/dL of HDL is considered a high HDL cholesterol level and optimal for protection against heart disease. Furthermore, the American Heart Association recommends an LDL (low density lipoprotein) cholesterol of less than 100 mg/dL as optimal, 100-129 mg/dL as near or above optimal, 130-159 mg/dL as borderline high, 160-189 mg/dL as high, and 190 mg/dL and above as very high. It is generally accepted that lowering the LDL cholesterol level also lower the risk of heart attach and stroke.

A low HDL cholesterol level is thought to accelerate the development of atherosclerosis because of impaired reverse cholesterol transport and the absence of other protective effects of HDL, such as decreased oxidation of other lipoproteins. Lipidemias are consequently associated with elevated oxidative stress and with increased level of lipid peroxidation products (Yang R L et al, J Clin Biochem Nutr 2008; 43:154-158) which activate numerous detrimental pathways (Spiteller G. Exp. Gerontol. 2001; 136:1425-1457).

Other disorders of liporegulation include generalized lipodystrophies, mutations of leptin and leptin receptor genes, and diet-induced obesity. Lipotoxicity of pancreatic cells, myocardium, and skeletal muscle leads, respectively, to type 2 diabetes, cardiomyopathy, and insulin resistance. In humans these abnormalities are commonly referred to as the metabolic syndrome. Reactive carbonyl products of lipid peroxidation may affect vulnerable targets differently. For example, it was shown that lipotoxicity in pancreatic cells is mainly modulated by conjugates of an omega-3 peroxidation product, HHE (Furakawa F et al, Pancreas 2001; 22:1900-1905). When lipids overaccumulate in nonadipose tissues during overnutrition, fatty acids enter deleterious pathways such as reactive carbonyl production, which causes apoptosis of lipid-laden cells such as cardiomyocytes. There is now substantial evidence that complications of human obesity may reflect lipotoxicity (Unger R H Ann Rev Med 2002; 53:319-336).

Chronic heart failure (CHF) causes substantial morbidity and mortality despite major therapeutic advances, such as the use of angiotensin-converting enzyme (ACE) inhibitors and Q-blockers. The main causes of CHF today are ischemic heart disease (IHD) and hypertension. A fundamental process in the progression to CHF (especially in patients with prior myocardial infarction [MI]) is a series of alterations in heart structure and function known as cardiac remodeling, that involves significant changes in gene expression and protein function, both in the extracellular matrix and in cardiomyocytes. Oxidative stress has long been implicated in clinical and experimental CHF. Indeed, lipid peroxidation plays a major role in the pathogenesis of ischemic damage and in conversion of reversible damage into irreversible damage through cardiomyocyte membrane destruction caused by lipid triad (Meerson F Z et al Basic Res Cardiol 1982; 77:465-485). Further supporting the role of lipid peroxidation, markers of oxidative stress are elevated in CHF patients and have been correlated with myocardial dysfunction and overall severity of heart failure. Mechanisms through which myocardial oxidative stress might impair cardiac function include, but are not limited to, oxidative damage to cellular proteins and membranes, thereby, inducing cellular dysfunction or death through apoptosis and necrosis (Grieve D J et al, Eur. Heart J. 2003; 24:2161-2163).

Moreover, ischemic heart disease is characterized by increased levels of PUFA peroxidation products, such as MDA in plasma (Bevan R J et al Free Rad Biol Med 2003; 35:517-527). Apart from the generation of toxic reactive carbonyl-containing lipid peroxidation products including, but not limited to, MDA, acrolein, HNE and HHE, ROS-initiated lipid damage also leads to trans-isomerisation of some cis double bonds in PUFAs. This process is also initiated by an ROS attack at bis-allylic sites, in particular, but not limited to, sulfur-based thiyl radicals. The resulting compounds have a detrimental effect on the membrane properties, changing membrane fluidity and making them leaky and unstable (Chatgilialoglu C et al Acc Chem Res. 2005; 38:441-448). In acute ischemic heart disease this mechanism may play an important role due to the formation of hydrogen peroxide, leading to lipid peroxidation and sulfhydryl group oxidation which generate membrane defects and result in intracellular calcium overload and cardiac contractile dysfunction in the stunned myocardium (Dhalla N S et al Can J Cardiol 1999; 15:587-593).

Atrial fibrillation, a heart beat irregularity, is linked to oxidative stress and enlargement of the heart's left atrium. Such an enlargement leads to atrial fibrillation. Left Ventricular Hypertrophy (LVH) is a common phase of heart damage leading to failure, mostly due to the loss of mitochondria through oxidative damage from reperfusion injury, aging, etc. ROS play a major role in the genesis and progression of coronary artery disease (CAD) with consequent myocardial ischemia and necrosis—a leading cause of heart failure worldwide. Lipid peroxidation is increased in CAD, as shown by MDA measurements in plasma free and total MDA levels. Moreover, free MDA values can help discriminate between unstable and chronic stable angina (Cavalca V et al, Clin Chem 2001; 47:887-892).

ROS activity in the vessel wall is thought to contribute to the formation of oxidized LDL, a major contributor to the pathogenesis of atherosclerosis. Indeed, oxidation of PUFA-rich low density lipoprotein (LDL) was suggested to be a major risk factor for atherosclerosis and for hypertension associated with atherosclerosis. HNE and other reactive carbonyl products of LDL oxidation elicit further oxidative damage and are involved in many downstream pathways including, but not limited to, modulating antioxidant gene expression (Siow R C et al Redox Rep 2007; 12:11-15) and increasing macrophage foam cell formation (Yun M R et al Free Rad Biol Med 2008; 45:177-183). Moreover, Angiotensin II (Ang-II) is involved in the oxidation of PUFAs, enhancing macrophage lipid peroxidation both in vivo and in vitro (Keidar S. Life Sci. 1998; 63:1-11). Despite the importance of oxidative stress in the etiology of atherosclerosis, the success of antioxidant therapies aiming to reduce lipid peroxidation has so far been limited (Stocker R et al Physiol Rev 2004; 84:1381-1478).

Cardiac hypertrophy can be either compensatory and adaptive or a maladaptive precursor to cardiac failure. Mounting evidence implicates ROS signaling in the genesis of cardiac hypertrophy. Myocardial lipotoxicity refers to the accumulation of intramyocardial lipids concomitant with contractile dysfunction, often associated with myocyte death. Recently it was shown that lipid accumulation and peroxidation is a significant feature of clinical heart failure (Unger R H Ann Rev Med 2002; 53:319-336). Lipid accumulation occurs when there is an imbalance between lipid uptake and β-oxidation, a circumstance that can occur via a variety of mechanisms. Lipid accumulation induces an increase in PPARα, a nuclear receptor that alters gene expression in response to lipids. PPARα increases fatty acid oxidation, and increased expression of PPARα has been associated with the development of cardiac dysfunction, including diabetic cardiomyopathy. Although the mechanism by which this occurs remains unclear, β-oxidation of fatty acids generates ROS and carbonyl lipid peroxidation products. Data suggests that ROS and carbonyl lipid peroxidation products play a role in the pathogenesis of PPARα-associated cardiomyopathies and lipotoxicity (Giordano F J, J Clin Invest 2005; 115:500-508).

Some aspects of this invention arise from: (1) an understanding that while essential PUFAs are vital for proper functioning of lipid membranes, and in particular of the mitochondrial membranes, their inherent drawback, i.e., the propensity to be oxidized by ROS with detrimental outcome, is implicated in lipidemias and cardiac-related risks; (2) antioxidants cannot prevent PUFA peroxidation due to stochastic nature of the process and the stability of PUFA peroxidation products (reactive carbonyls) to antioxidant treatment, and (3) the ROS-driven damage of oxidation-prone sites within PUFAs may be overcome by using an approach that makes them less amenable to such oxidations, without compromising any of their beneficial physical properties. Some aspects of this invention describe the use of the isotope effect to achieve this, only at sites in essential PUFAs and PUFA precursors that matter most for oxidation, while other aspects contemplate other sites in addition to those that matter most for oxidation.

Isotopically labeled embodiments should have minimal or non-existent effects on important biological processes. For example, the natural abundance of isotopes present in biological substrates implies that low levels of isotopically labeled compounds should have negligible effects on biological processes. Additionally, hydrogen atoms are incorporated into biological substrates from water, and is it known that the consumption of D₂O, or heavy water, does not pose a health threat to humans. See, e.g., “Physiological effect of heavy water.” Elements and isotopes: formation, transformation, distribution. Dordrecht: Kluwer Acad. Publ. (2003) pp. 111-112 (indicating that a 70 kg person might drink 4.8 liters of heavy water without serious consequences). Moreover, many isotopically labeled compounds are approved by the U.S. Food & Drug Administration for diagnostic and treatment purposes.

It will be appreciated by those skilful in the art that the same effect can be achieved by protecting oxidation-prone positions within PUFAs using other chemical approaches. Certain PUFA mimetics, while possessing structural similarity with natural PUFAs, will nevertheless be stable to ROS-driven oxidation due to structural reinforcement.

Compositions:

In some embodiments, an isotopically modified polyunsaturated fatty acid or a mimetic refers to a compound having structural similarity to a naturally occurring PUFA that is stabilized chemically or by reinforcement with one or more isotopes, for example ¹³C and/or deuterium. Generally, if deuterium is used for reinforcement, one or both hydrogens on a methylene group may be reinforced.

Some aspects of this invention provide compounds that are analogues of essential PUFAs with one, several, or all bis-allylic positions substituted with heavy isotopes. In some embodiments, the CH₂ groups, which will become the bis-allylic position in a PUFA upon enzymatic conversion, are substituted with one or two heavy isotopes. Such compounds are useful for the prevention or treatment of diseases in which PUFA oxidation is a factor or can contribute to disease progression.

The bis-allylic position generally refers to the position of the polyunsaturated fatty acid or mimetic thereof that corresponds to the methylene groups of 1,4-diene systems. The pro-bis-allylic position refers to the methylene group that becomes the bis-allylic position upon enzymatic desaturation.

In some embodiments, the chemical identity of PUFAs, i.e., the chemical structure without regard to the isotope substitutions or substitutions that mimic isotope substitutions, remains the same upon ingestion. For instance, the chemical identity of essential PUFAs, that is, PUFAs that mammals such as humans do not generally synthesize, may remain identical upon ingestion. In some cases, however, PUFAs may be further extended/desaturated in mammals, thus changing their chemical identity upon ingestion. Similarly with mimetics, the chemical identity may remain unchanged or may be subject to similar extension/desaturation. In some embodiments, PUFAs that are extended, and optionally desaturated, upon ingestion and further metabolism may be referred to as higher homologs.

In some embodiments, naturally-occurring abundance level refers to the level of isotopes, for example ¹³C and/or deuterium that may be incorporated into PUFAs that would be relative to the natural abundance of the isotope in nature. For example, ¹³C has a natural abundance of roughly 1% ¹³C atoms in total carbon atoms. Thus, the relative percentage of carbon having greater than the natural abundance of ¹³C in PUFAs may have greater than the natural abundance level of roughly 1% of its total carbon atoms reinforced with ¹³C, such as 2%, but preferably about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of ¹³C with respect to one or more carbon atoms in each PUFA molecule. In other embodiments, the percentage of total carbon atoms reinforced with ¹³C is at least 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%.

Regarding hydrogen, in some embodiments, deuterium has a natural abundance of roughly 0.0156% of all naturally occurring hydrogen in the oceans on earth. Thus, a PUFA having greater that the natural abundance of deuterium may have greater than this level or greater than the natural abundance level of roughly 0.0156% of its hydrogen atoms reinforced with deuterium, such as 0.02%, but preferably about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of deuterium with respect to one or more hydrogen atoms in each PUFA molecule. In other embodiments, the percentage of total hydrogen atoms reinforced with deuterium is at least 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%.

In some aspects, a composition of PUFAs contains both isotopically modified PUFAs and isotopically unmodified PUFAs. The isotopic purity is a comparison between a) the relative number of molecules of isotopically modified PUFAs, and b) the total molecules of both isotopically modified PUFAs and PUFAs with no heavy atoms. In some embodiments, the isotopic purity refers to PUFAs that are otherwise the same except for the heavy atoms.

In some embodiments, isotopic purity refers to the percentage of molecules of an isotopically modified PUFAs in the composition relative to the total number of molecules of the isotopically modified PUFAs plus PUFAs with no heavy atoms. For example, the isotopic purity may be about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the molecules of isotopically modified PUFAs relative to the total number of molecules of both the isotopically modified PUFAs plus PUFAs with no heavy atoms. In other embodiments, the isotopic purity is at least 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%. In some embodiments, isotopic purity of the PUFAs may be from about 10%-100%, 10%-95%, 10%-90%, 10%-85%, 10%-80%, 10%-75%, 10%-70%, 10%-65%, 10%-60%, 10%-55%, 10%-50%, 10%-45%, 10%-40%, 10%-35%, 10%-30%, 10%-25%, or 10%-20% of the total number of molecules of the PUFAs in the composition. In other embodiments, isotopic purity of the PUFAs may be from about 15%-100%, 15%-95%, 15%-90%, 15%-85%, 15%-80%, 15%-75%, 15%-70%, 15%-65%, 15%-60%, 15%-55%, 15%-50%, 15%-45%, 15%-40%, 15%-35%, 15%-30%, 15%-25%, or 15%-20% of the total number of molecules of the PUFAs in the composition. In some embodiments, isotopic purity of the PUFAs may be from about 20%-100%, 20%-95%, 20%-90%, 20%-85%, 20%-80%, 20%-75%, 20%-70%, 20%-65%, 20%-60%, 20%-55%, 20%-50%, 20%-45%, 20%-40%, 20%-35%, 20%-30%, or 20%-25% of the total number of molecules of the PUFAs in the composition. Two molecules of an isotopically modified PUFA out of a total of 100 total molecules of isotopically modified PUFAs plus PUFAs with no heavy atoms will have 2% isotopic purity, regardless of the number of heavy atoms the two isotopically modified molecules contain.

In some aspects, an isotopically modified PUFA molecule may contain one deuterium atom, such as when one of the two hydrogens in a methylene group is replaced by deuterium, and thus may be referred to as a “D1” PUFA. Similarly, an isotopically modified PUFA molecule may contain two deuterium atoms, such as when the two hydrogens in a methylene group are both replaced by deuterium, and thus may be referred to as a “D2” PUFA. Similarly, an isotopically modified PUFA molecule may contain three deuterium atoms and may be referred to as a “D3” PUFA. Similarly, an isotopically modified PUFA molecule may contain four deuterium atoms and may be referred to as a “D4” PUFA. In some embodiments, an isotopically modified PUFA molecule may contain five deuterium atoms or six deuterium atoms and may be referred to as a “D5” or “D6” PUFA, respectively.

The number of heavy atoms in a molecule, or the isotopic load, may vary. For example, a molecule with a relatively low isotopic load may contain about 1, 2, 3, 4, 5, or 6 deuterium atoms. A molecule with a moderate isotopic load may contain about 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 deuterium atoms. In a molecule with a very high load, every hydrogen may be replaced with a deuterium. Thus, the isotopic load refers to the percentage of heavy atoms in each PUFA molecule. For example, the isotopic load may be about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the number of the same type of atoms in comparison to a PUFA with no heavy atoms of the same type (e.g. hydrogen would be the “same type” as deuterium). In some embodiments, the isotopic load is at least 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%. Unintended side effects are expected to be reduced where there is high isotopic purity in a PUFA composition but low isotopic load in a given molecule. For example, the metabolic pathways will likely be less affected by using a PUFA composition with high isotopic purity but low isotopic load.

One will readily appreciate that when one of the two hydrogens of a methylene group is replaced with a deuterium atom, the resultant compound may possess a stereocenter. In some embodiments, it may be desirable to use racemic compounds. In other embodiments, it may be desirable to use enantiomerically pure compounds. In additional embodiments, it may be desirable to use diastereomerically pure compounds. In some embodiments, it may be desirable to use mixtures of compounds having enantiomeric excesses and/or diastereomeric excesses of about 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%. In other embodiments, the enantiomeric excesses and/or diastereomeric excesses is at least 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%. In some embodiments, it may be preferable to utilize stereochemically pure enantiomers and/or diastereomers of embodiments—such as when contact with chiral molecules is being targeted for attenuating oxidative damage. However, in many circumstances, non-chiral molecules are being targeted for attenuating oxidative damage. In such circumstances, embodiments may be utilized without concern for their stereochemical purity. Moreover, in some embodiments, mixtures of enantiomers and diastereomers may be used even when the compounds are targeting chiral molecules for attenuating oxidative damage.

In some aspects, isotopically modified PUFAs impart an amount of heavy atoms in a particular tissue. Thus, in some aspects, the amount of heavy molecules will be a particular percentage of the same type of molecules in a tissue. For example, the number of heavy molecules may be about 1%-100% of the total amount of the same type of molecules. In some aspects, 10-50% the molecules are substituted with the same type of heavy molecules.

In some embodiments, a compound with the same chemical bonding structure as an essential PUFA but with a different isotopic composition at particular positions will have significantly and usefully different chemical properties from the unsubstituted compound. The particular positions with respect to oxidation, including oxidation by ROS, comprise bis-allylic positions of essential polyunsaturated fatty acids and their derivatives, as shown in FIG. 1 . The essential PUFAs isotopically reinforced at bis-allylic positions shown below will be more stable to the oxidation. Accordingly, some aspects of the invention provide for particular methods of using compounds of Formula (1) or salts thereof, whereas the sites can be further reinforced with carbon-13. R¹=alkyl, H, or cation; m=1-10; n=1-5, where at each bis-allylic position, one or both Y atoms are deuterium atoms, for example,

11,11-Dideutero-cis,cis-9,12-Octadecadienoic acid (11,11-Dideutero-(9Z,12Z)-9,12-Octadecadienoic acid; D2-LA); and 11,11,14,14-Tetradeutero-cis,cis,cis-9,12,15-Octadecatrienoic acid (11,11,14,14-Tetradeutero-(9Z,12Z,15Z)-9,12,15-Octadecatrienoic acid; D4-ALA). In some embodiments, said positions, in addition to deuteration, can be further reinforced by carbon-13, each at levels of isotope abundance above the naturally-occurring abundance level. All other carbon-hydrogen bonds in the PUFA molecule may optionally contain deuterium and/or carbon-13 at, or above, the natural abundance level.

Essential PUFAs are biochemically converted into higher homologues by desaturation and elongation. Therefore, some sites which are not bis-allylic in the precursor PUFAs will become bis-allylic upon biochemical transformation. Such sites then become sensitive to oxidation, including oxidation by ROS. In a further embodiment, such pro-bis-allylic sites, in addition to existing bis-allylic sites are reinforced by isotope substitution as shown below. Accordingly, this aspect of the invention provides for the use of compounds of Formula (2) or salt thereof, where at each bis-allylic position, and at each pro-bis-allylic position, one or more of X or Y atoms may be deuterium atoms. R1=alkyl, cation, or H; m=1-10; n=1-5; p=1-10.

Said positions, in addition to deuteration, can be further reinforced by carbon-13, each at levels of isotope abundance above the naturally-occurring abundance level. All other carbon-hydrogen bonds in the PUFA molecule may contain optionally deuterium and/or carbon-13 at or above the natural abundance level.

Oxidation of PUFAs at different bis-allylic sites gives rise to different sets of oxidation products. For example, 4-HNE is formed from n-6 PUFAs whereas 4-HHE is formed from n-3 PUFAs (Negre-Salvayre A, et al. Brit. J. Pharmacol. 2008; 153:6-20). The products of such oxidation possess different regulatory, toxic, signaling, etc. properties. It is therefore desirable to control the relative extent of such oxidations. Accordingly, some aspects of the invention provide for the use of compounds of Formula (3), or salt thereof, differentially reinforced with heavy stable isotopes at selected bis-allylic or pro-bis-allylic positions, to control the relative yield of oxidation at different sites, as shown below, such that any of the pairs of Y¹-Y^(n) and/or X¹-X^(m) at the bis-allylic or pro-bis-allylic positions of PUFAs may contain deuterium atoms. R1=alkyl, cation, or H; m=1-10; n=1-6; p=1-10

Said positions, in addition to deuteration, can be further reinforced by carbon-13. All other carbon-hydrogen bonds in the PUFA molecule may contain deuterium at, or above the natural abundance level. It will be appreciated that the break lines in the structure shown above represents a PUFA with a varying number of double bonds, a varying number of total carbons, and a varying combination of isotope reinforced bis-allylic and pro-bis-allylic sites.

Exact structures of compounds illustrated above are shown below that provide for both isotope reinforced n-3 (omega-3) and n-6 (omega-6) essential polyunsaturated fatty acids, and the PUFAs made from them biochemically by desaturation/elongation. Any one of these compounds may be used to slow oxidation. In the following compounds, the PUFAs are isotopically reinforced at oxidation sensitive sites and/or sites that may become oxidation sensitive upon biochemical desaturation/elongation. R¹ may be H, alkyl, or cation; R² may be H or D; * represents either ¹²C or ¹³C.

D-Linoleic acids include:

The per-deuterated linoleic acid below may be produced by microbiological methods, for example by growing in media containing deuterium and/or carbon-13.

D-Arachidonic acids include:

The per-deuterated arachidonic acid below may be produced by microbiological methods, such as by growing in media containing deuterium and/or carbon-13.

D-Linolenic acids include:

Per-deuterated linolenic acid below may be produced by microbiological methods, such as growing in media containing deuterium and/or carbon-13.

In some aspects of the invention, any PUFAs, whether essential or not, that are capable of being taken up from diet and used in the body, can be utilized. In the case of essential or non-essential PUFAs or precursors, the supplemented stabilized materials can compete with other dietary uptake and bio-manufacture to reduce the available disease-causing species concentrations.

In some aspects of the invention, the PUFAs isotopically reinforced at oxidation sensitive positions as described by way of the structures above are heavy isotope enriched at said positions as compared to the natural abundance of the appropriate isotope, deuterium and/or carbon-13.

In some embodiments, the disclosed compounds are enriched to 99% isotope purity or more. In some embodiments, the heavy isotope enrichment at said positions is between 50%-99% deuterium and/or carbon-13.

In some embodiments, the modified fatty acids, when dosed via diet as drugs or supplements, may be dosed as pro-drugs, including, but not limited to, non-toxic and pharmaceutically suitable esters of the parent fatty acid or mimetic, such as an ethyl ester or glyceryl ester. This ester assists in tolerance of the drug in the gut, assists in digestion, and relies on the high levels of esterases in the intestines to de-esterify the ester pro-drugs into the active acid form of the drug which adsorbs. Hence, in some embodiments, the invention encompasses the pro-drug esters of the modified fatty acids herein. Examples of this type of drug in the market, nutrition, and clinical trials literature, including Glaxo's Lovaza, (mixtures of omega 3 fatty acid esters, EPA, DHA, and alpha-linolenic acid), Abbott's Omacor (omega-3-fatty acid esters), and most fish oil supplements (DHA and EPA esters). In some aspects, incorporation of the ester pro-drugs into tissues or cells refers to the incorporation of the modified parent PUFA as it would be used as a bodily constituent.

In some embodiments, stabilized compositions mimic natural occurring fatty acids without changing their elemental composition. For example, the substituent may retain the chemical valence shell. Some embodiments include naturally occurring fatty acids, mimetics, and their ester pro-drugs, that are modified chemically to be effective at preventing specific disease mechanisms, but are modified in a way (such as isotopic substitution) that does not change the elemental composition of the material. For example, deuterium is a form of the same element hydrogen. In some aspects, these compounds maintain elemental composition and are stabilized against oxidation. Some compounds that are stabilized against oxidation are stabilized at oxidation sensitive loci. Some compounds are stabilized against oxidation via heavy isotope substitution, then at bis-allylic carbon hydrogen bonds, etc.

In a further embodiment, oxidation-prone bis-allylic sites of PUFAs can be protected against hydrogen abstraction by moving bis-allylic hydrogen-activating double bonds further apart, thus eliminating the bis-allylic positions while retaining certain PUFA fluidity as shown below. These PUFA mimetics have no bis-allylic positions.

In a further embodiment, oxidation-prone bis-allylic sites of PUFAs can be protected against hydrogen abstraction by using heteroatoms with valence II, thus eliminating the bis-allylic hydrogens as shown below. These PUFA mimetics also have no bis-allylic hydrogens.

In a further embodiment, PUFA mimetics, i.e. compounds structurally similar to natural PUFAs but unable to get oxidized because of the structural differences, can be employed for the above mentioned purposes. Oxidation-prone bis-allylic sites of PUFAs can be protected against hydrogen abstraction by di-methylation or halogenation as shown below. The hydrogen atoms on the methyl groups may optionally be halogens, such as fluorine, or deuterium. These PUFA mimetics are dimethylated at bis-allylic sites.

In a further embodiment, oxidation-prone bis-allylic sites of PUFAs can be protected against hydrogen abstraction by alkylation as shown below. These PUFA mimetics are dialkylated at bis-allylic sites.

In a further embodiment, cyclopropyl groups can be used instead of double bonds, thus rendering the acids certain fluidity while eliminating the bis-allylic sites as shown below. These PUFA mimetics have cyclopropyl groups instead of double bonds.

In a further embodiment, 1,2-substituted cyclobutyl groups in appropriate conformation can be used instead of double bonds, thus rendering the acids certain fluidity while eliminating the bis-allylic sites as shown below. These PUFA mimetics have 1,2-cyclobutyl groups instead of double bonds.

In a modification of the previous embodiment of mimetics with 1,2-cyclobutyl groups instead of double bonds, 1,3-substituted cyclobutyl groups in appropriate conformation can be used instead of double bonds, thus rendering the acids certain fluidity while eliminating the bis-allylic sites. The following PUFA mimetics have 1,3-cyclobutyl groups instead of double bonds.

It is a well known principle in medicinal chemistry that certain functional groups are isosteric and/or bioisosteric with certain other functional groups. Bioisosteres are substituents or groups with similar physical or chemical properties which produce broadly similar biological properties to a chemical compound. For example, well known isosteres and/or bioisosteres for hydrogen include halogens such as fluorine; isosteres and/or bioisosteres of alkenes include alkynes, phenyl rings, cyclopropyl rings, cyclobutyl rings, cyclopentyl rings, cyclohexyl rings, thioethers, and the like; isosteres and/or bioisosteres of carbonyls include sulfoxides, sulfones, thiocarbonyls, and the like; isosteres and/or bioisosteres of esters include amides, sulfonic acid esters, sulfonamides, sulfinyl acid esters, sulfinylamindes, and the like. Consequently, PUFA mimetics also include compounds having isosteric and/or bioisosteric functional groups.

It is contemplated that it may be useful to formulate PUFAs and/or PUFA mimetics as a pro-drug for use in the invention. A pro-drug is a pharmacological substance may itself have biological activity, but upon administration the pro-drug is metabolized into a form that also exerts biological activity. Many different types of pro-drugs are known and they can be classified into two major types based upon their cellular sites of metabolism. Type I pro-drugs are those that are metabolized intracellularly, while Type II are those that are metabolized extracellularly. It is well-known that carboxylic acids may be converted to esters and various other functional groups to enhance pharmacokinetics such as absorption, distribution, metabolism, and excretion. Esters are a well-known pro-drug form of carboxylic acids formed by the condensation of an alcohol (or its chemical equivalent) with a carboxylic acid (or its chemical equivalent). In some embodiments, alcohols (or their chemical equivalent) for incorporation into pro-drugs of PUFAs include pharmaceutically acceptable alcohols or chemicals that upon metabolism yield pharmaceutically acceptable alcohols. Such alcohols include, but are not limited to, propylene glycol, ethanol, isopropanol, 2-(2-ethoxyethoxy)ethanol (Transcutol®, Gattefosse, Westwood, N.J. 07675), benzyl alcohol, glycerol, polyethylene glycol 200, polyethylene glycol 300, or polyethylene glycol 400; polyoxyethylene castor oil derivatives (for example, polyoxyethyleneglyceroltriricinoleate or polyoxyl 35 castor oil (Cremophor®EL, BASF Corp.), polyoxyethyleneglycerol oxystearate (Cremophor®RH 40 (polyethyleneglycol 40 hydrogenated castor oil) or Cremophor®RH 60 (polyethyleneglycol 60 hydrogenated castor oil), BASF Corp.)); saturated polyglycolized glycerides (for example, Gelucire® 35/10, Gelucire® 44/14, Gelucire® 46/07, Gelucire@ 50/13 or Gelucire® 53/10, available from Gattefosse, Westwood, N.J. 07675); polyoxyethylene alkyl ethers (for example, cetomacrogol 1000); polyoxyethylene stearates (for example, PEG-6 stearate, PEG-8 stearate, polyoxyl 40 stearate NF, polyoxyethyl 50 stearate NF, PEG-12 stearate, PEG-20 stearate, PEG-100 stearate, PEG-12 distearate, PEG-32 distearate, or PEG-150 distearate); ethyl oleate, isopropyl palmitate, isopropyl myristate; dimethyl isosorbide; N-methylpyrrolidinone; parafin; cholesterol; lecithin; suppository bases; pharmaceutically acceptable waxes (for example, carnauba wax, yellow wax, white wax, microcrystalline wax, or emulsifying wax); pharmaceutically acceptable silicon fluids; soribitan fatty acid esters (including sorbitan laurate, sorbitan oleate, sorbitan palmitate, or sorbitan stearate); pharmaceutically acceptable saturated fats or pharmaceutically acceptable saturated oils (for example, hydrogenated castor oil (glyceryl-tris-12-hydroxystearate), cetyl esters wax (a mixture of primarily C14-C18 saturated esters of C14-C18 saturated fatty acids having a melting range of about 43°-47° C.), or glyceryl monostearate).

In some embodiments, the fatty acid pro-drug is represented by the ester P B, wherein the radical P is a PUFA and the radical B is a biologically acceptable molecule. Thus, cleavage of the ester P-B affords a PUFA and a biologically acceptable molecule. Such cleavage may be induced by acids, bases, oxidizing agents, and/or reducing agents. Examples of biologically acceptable molecules include, but are not limited to, nutritional materials, peptides, amino acids, proteins, carbohydrates (including monosaccharides, disaccharides, polysaccharides, glycosaminoglycans, and oligosaccharides), nucleotides, nucleosides, lipids (including mono-, di- and tri-substituted glycerols, glycerophospholipids, sphingolipids, and steroids).

In some embodiments, alcohols (or their chemical equivalent) for incorporation into pro-drugs of PUFAs include alcohols with 1 to 50 carbon atoms (“C₁₋₅₀ alcohols”), C₁₋₄₅ alcohols, C₁₋₄₀ alcohols, C₁₋₃₅ alcohols, C₁₋₃₀ alcohols, C₁₋₂₅ alcohols, C₁₋₂₀ alcohols, C₁₋₁₅ alcohols, C₁₋₁₀ alcohols, C₁₋₆ alcohols (whenever it appears herein, a numerical range such as “1-50” refers to each integer in the given range; e.g., “1 to 50 carbon atoms” means that the alkyl group may consist of 1 carbon atom, 2 carbon atoms, 3 carbon atoms, etc., up to and including 50 carbon atoms, although the present definition also covers the occurrence of the term “alkyl” where no numerical range is designated). Such alcohols may be branched, unbranched, saturated, unsaturated, polyunsaturated and/or include one or more heteroatoms such as nitrogen, oxygen, sulfur, phosphorus, boron, silicone, fluorine, chlorine, bromine, or iodine. Exemplary alcohols include methyl, ethyl, propyl, iso-propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, perfluromethyl, perchloromethyl, perfluoro-tert-butyl, perchloro-tert-butyl, and benzyl alcohols as well as ether alcohols such as polyethylene glycols. In some embodiments, the alcohol contains a charged species. Such species may be anionic or cationic. In some embodiments, the species is a positively charged phosphorus atom. In other embodiments, the positively charged phosphorus atom is a phosphonium cation. In other embodiments the charged species is a primary, secondary, tertiary, or quaternary ammonium cation.

In some embodiments, alcohols (or their chemical equivalent) for incorporation into pro-drugs of PUFAs include polyalcohols such as diols, triols, tetra-ols, penta-ols, etc. Examples of polyalcohols include ethylene glycol, propylene glycol, 1,3-butylene glycol, polyethylene glycol, methylpropanediol, ethoxydiglycol, hexylene glycol, dipropylene glycol glycerol, and carbohydrates. Esters formed from polyalcohols and PUFAs may be mono-esters, di-esters, tri-esters, etc. In some embodiments, multiply esterified polyalcohols are esterified with the same PUFAs. In other embodiments, multiply esterified polyalcohols are esterified with different PUFAs. In some embodiments, the different PUFAs are stabilized in the same manner. In other embodiments, the different PUFAs are stabilized in different manners (such as deuterium substitution in one PUFA and ¹³C substitution in another PUFA). In some embodiments, one or more PUFAs is an omega-3 fatty acid and one or more PUFAs is an omega-6 fatty acid.

It is also contemplated that it may be useful to formulate PUFAs and/or PUFA mimetics and/or PUFA pro-drugs as salts for use in the invention. For example, the use of salt formation as a means of tailoring the properties of pharmaceutical compounds is well known. See Stahl et al., Handbook of pharmaceutical salts: Properties, selection and use (2002) Weinheim/Zurich: Wiley-VCH/VHCA; Gould, Salt selection for basic drugs, Int. J. Pharm. (1986), 33:201-217. Salt formation can be used to increase or decrease solubility, to improve stability or toxicity, and to reduce hygroscopicity of a drug product.

Formulation of PUFAs and/or PUFA mimetics and/or PUFA pro-drugs as salts includes, but is not limited to, the use of basic inorganic salt forming agents, basic organic salt forming agents, and salt forming agents containing both acidic and basic functional groups. Various useful inorganic bases for forming salts include, but are not limited to, alkali metal salts such as salts of lithium, sodium, potassium rubidium, cesium, and francium, and alkaline earth metal salts such as berylium, magnesium, calcium, strontium, barium, and radium, and metals such as aluminum. These inorganic bases may further include counterions such as carbonates, hydrogen carbonates, sulfates, hydrogen sulfates, sulfites, hydrogen sulfites, phosphates, hydrogen phosphates, dihydrogen phosphates, phosphites, hydrogen phosphites, hydroxides, oxides, sulfides, alkoxides such as methoxide, ethoxide, and t-butoxide, and the like. Various useful organic bases for forming salts include, but are not limited to, amino acids, basic amino acids such as arginine, lysine, ornithine and the like, ammonia, alkylamines such as methylamine, ethylamine, dimethylamine, diethylamine, trimethylamine, triethylamine and the like, heterocyclic amines such as pyridine, picoline and the like, alkanolamines such as ethanolamine, diethanolamine, triethanolamine and the like, diethylaminoethanol, dimethylaminoethanol, N-methylglucamine, dicyclohexylamine, N,N′-dibenzylethylenediamine, ethylenediamine, piperazine, choline, trolamine, imidazole, diolamine, betaine, tromethamine, meglumine, chloroprocain, procaine, and the like.

Salt formulations of PUFAs and/or PUFA mimetics and/or PUFA pro-drugs include, but are not limited to, pharmaceutically acceptable basic inorganic salts, basic organic salts, and/or organic compounds having both acidic and basic functional groups. Pharmaceutically acceptable salts are well known in the art and include many of the above-recited inorganic and organic bases. Pharmaceutically acceptable salts further include salts and salt-forming agents found in drugs approved by the Food and Drug Administration and foreign regulatory agencies. Pharmaceutically acceptable organic cations for incorporation include, but are not limited to, benzathine, chloroprocaine, choline, diethanolamine, ethylenediamine, meglumine, procaine, benethamine, clemizole, diethylamine, piperazine, and tromethamine. Pharmaceutically acceptable metallic cations for incorporation include, but are not limited to, aluminum, calcium, lithium, magnesium, potassium, sodium, zinc, barium, and bismuth. Additional salt-forming agents include, but are not limited to, arginine, betaine, carnitine, diethylamine, L-glutamine, 2-(4-imidazolyl)ethylamine, isobutanolamine, lysine, N-methylpiperazine, morpholine, and theobromine.

Moreover, several lists of pharmaceutically approved counterions exists. See Bighley et al., Salt forms of drugs and absorption. 1996 In: Swarbrick J. et al. eds. Encyclopaedia of pharmaceutical technology, Vol. 13 New York: Marcel Dekker, Inc. pp 453-499; Gould, P. L., Int. J. Pharm. 1986, 33, 201-217; Berge, J. Pharm. Sci. 1977, 66, 1-19; Heinrich Stahl P., Wermuch C. G. (editors), Handbook of Pharmaceutical Salts, IUPAC, 2002; Stahl et al., Handbook of pharmaceutical salts: Properties, selection and use (2002) Weinheim/Zurich: Wiley-VCH/VHCA, all of which are incorporated herein by reference.

It may be unnecessary to substitute all isotopically unmodified PUFAs, such as non-deuterated PUFAs, with isotopically modified PUFAs such as deuterated PUFAs. In some embodiments, is preferable to have sufficient isotopically modified PUFAs such as D-PUFAs in the membrane to prevent unmodified PUFAs such as H—PUFAs from sustaining a chain reaction of self-oxidation. During self-oxidation, when one PUFA oxidizes, and there is a non-oxidized PUFA in the vicinity, the non-oxidized PUFA can get oxidized by the oxidized PUFA. This may also be referred to as autooxidation. In some instances, if there is a low concentration, for example “dilute” H-PUFAs in the membrane with D-PUFAs, this oxidation cycle may be broken due to the distance separating H-PUFAs. In some embodiments, the concentration of isotopically modified PUFAs is present in a sufficient amount to maintain autooxidation chain reaction. To break the autooxidation chain reaction, for example, 1-60%, 5-50%, or 15-35% of the total molecules of the same type are in the membrane. This may be measured by IRMS (isotope ratio mass spectrometry).

A further aspect of the invention provides a dietary, supplementary or pharmaceutical composition of the active compounds. In some embodiments, the dietary, supplementary, or pharmaceutical composition may comprise a salt of the active compound.

Various useful inorganic bases for forming salts include, but are not limited to, alkali metal salts such as salts of lithium, sodium, potassium rubidium, cesium, and francium, and alkaline earth metal salts such as berylium, magnesium, calcium, strontium, barium, and radium, and metals such as aluminum. These inorganic bases may further include counterions such as carbonates, hydrogen carbonates, sulfates, hydrogen sulfates, sulfites, hydrogen sulfites, phosphates, hydrogen phosphates, dihydrogen phosphates, phosphites, hydrogen phosphites, hydroxides, oxides, sulfides, alkoxides such as methoxide, ethoxide, and t-butoxide, and the like.

Various useful organic bases for forming salts include, but are not limited to, amino acids; basic amino acids such as arginine, lysine, ornithine and the like; ammonia; ammonium hydroxide; alkylamines such as methylamine, ethylamine, dimethylamine, diethylamine, trimethylamine, triethylamine and the like; heterocyclic amines such as pyridine, picoline and the like; alkanolamines such as ethanolamine, diethanolamine, triethanolamine and the like, diethylaminoethanol, dimethylaminoethanol; N-methylglucamine; dicyclohexylamine; N,N′-dibenzylethylenediamine; ethylenediamine; piperazine; choline; trolamine; imidazole; diolamine; betaine; tromethamine; meglumine; chloroprocain; procaine; and the like.

Salts of active compounds may include, but are not limited to, pharmaceutically acceptable salts. Pharmaceutically acceptable salts are well known in the art and include many of the above-listed salt-forming agents. Pharmaceutically acceptable salts further include salts and salt-forming agents of the type present in drugs approved by the Food and Drug Administration and foreign regulatory agencies.

Pharmaceutically acceptable organic cations for incorporation into a salt of an active compound include, but are not limited to, benzathine, chloroprocaine, choline, diethanolamine, ethylenediamine, meglumine, procaine, benethamine, clemizole, diethylamine, piperazine, and tromethamine.

Pharmaceutically acceptable metallic cations for incorporation into a salt of an active compound include, but are not limited to, aluminum, calcium, lithium, magnesium, potassium, sodium, zinc, barium, and bismuth.

Additional salt-forming agents having potential usefulness as forming salts include, but are not limited to, acetylaminoacetic acid, N-acetyl-L-asparagine, N-acetylcystine, arginine, betaine, carnitine, L-glutamine, 2-(4-imidazolyl)ethylamine, isobutanolamine, lysine, N-methylpiperazine, and morpholine.

Moreover, several lists of pharmaceutically approved counterions exists. See Bighley et al., Salt forms of drugs and absorption. 1996 In: Swarbrick J. et al. eds. Encyclopaedia of pharmaceutical technology, Vol. 13 New York: Marcel Dekker, Inc. pp 453-499; Gould, P. L., Int. J. Pharm. 1986, 33, 201-217; Berge, J. Pharm. Sci. 1977, 66, 1-19; Heinrich Stahl P., Wermuch C. G. (editors), Handbook of Pharmaceutical Salts, TUPAC, 2002; Stahl et al., Handbook of pharmaceutical salts: Properties, selection and use (2002) Weinheim/Zurich: Wiley-VCH/VHCA, all of which are incorporated herein by reference.

Co-Administration

In some embodiments, the compounds disclosed herein are administered in combination. For example, in some embodiments, two, three, four, and/or five or more stabilized compounds are administered together. In some embodiments, stabilized compounds are administered in approximately similar amounts. In other embodiments, stabilized compounds are administered in differing amounts. For example, any one of two or more compounds in a mixture may represent about 1% to about 99% of a mixture, about 5% to about 95% of a mixture, about 10% to about 90% of a mixture, about 15% to about 85% of a mixture, about 20% to about 80% of a mixture, about 25% to about 75% of a mixture, about 30% to about 70% of a mixture, about 35% to about 65% of a mixture, about 40% to about 60% of a mixture, about 40% to about 60% of a mixture, about 45% to about 55% of a mixture, and/or about 50% of a mixture. In other embodiments, any one of two or more compounds in a mixture may represent about: 5% 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 65%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of a mixture.

Although antioxidants cannot cancel the negative effects of PUFA peroxidation due to the stochastic nature of the process and the stability of PUFA peroxidation products (reactive carbonyls) to antioxidant treatment, co-administration of antioxidants with compositions resistant to oxidation, such as those described herein, may prove beneficial for treating oxidative stress-related disorders.

Certain antioxidants contemplated as useful for co-administration include the following: vitamins, such as vitamin C and vitamin E; glutathione, lipoic acid, uric acid, carotenes, lycopene, lutein, anthocyanins, oxalic acid, phytic acid, tannins, coenzyme Q, melatonin, tocopherols, tocotrienols, polyphenols including resveratrol, flavonoids, selenium, eugenol, idebenone, mitoquinone, mitoquinol, ubiquinone, Szeto-Schiller peptides, and mitochondrial-targeted antioxidants. When not explicitly mentioned, quinone derivatives of the aforementioned antioxidants are also contemplated as useful for co-administration.

In some embodiments, stabilized compounds are administered with compounds that upregulate antioxidant genes. In other embodiments, stabilized compounds are administered with compounds that affect signaling pathways, such as the Keap1/Nrf2/ARE signaling pathway, thereby resulting in the production of anti-inflammatory and/or antioxidant proteins, such as heme oxygenase-1 (HO-1). In some embodiments, stabilized compounds are administered with antioxidant inflammation modulators. Antioxidant inflammation modulators suppress pro-oxidant and/or pro-inflammatory transcription factors. In some embodiments, antioxidant inflammation modulators are activators of the transcription factor Nrf2. Nrf2 activation promotes the antioxidant, detoxification, and anti-inflammatory genes upregulation. In other embodiments, antioxidant inflammation modulators suppress NF-κB. In some embodiments, antioxidant inflammation modulators suppress STAT3. In other embodiments, stabilized compounds are administered with compounds that affect histone deacetylase activity. In some embodiments, stabilized compounds are administered with compounds that bind to antioxidant response elements (ARE). In other embodiments, stabilized compounds are administered with bardoxolone methyl (2-cyano-3,12-dioxooleane-1,9(11)-dien-28-oic acid methyl ester) as the antioxidant inflammation modulator. In some embodiments, the antioxidant inflammation modulator is 2-cyano-3,12-dioxooleane-1,9(11)-dien-28-oic acid, or a pharmaceutically acceptable ester thereof. In other embodiments, the antioxidant inflammation modulator is an amide of 2-cyano-3,12-dioxooleane-1,9(11)-dien-28-oic acid. In some embodiments, the antioxidant inflammation modulator is a triterpenoid. In other embodiments, the antioxidant inflammation modulator is selected from the following compounds:

Additional antioxidants believed to be useful in co-administration therapies include those compounds disclosed in U.S. Pat. Nos. 6,331,532; 7,179,928; 7,232,809; 7,888,334; 7,888,335; 7,432,305; 7,470,798; and 7,514,461; and U.S. Patent Application Nos. 20020052342; 20030069208; 20040106579; 20050043553; 20050245487; 20060229278; 20070238709; 20070270381; 20080161267; 20080275005; 20090258841; 20100029706; and 20110046219; in which the compounds disclosed therein are incorporated by reference. These compounds are mitochondrially-targeted compounds and include, but are not limited to:

Compounds of Formulas I or II

wherein R₁ and R₂ are independently selected from —C₁-C₄ alkyl, —C₁-C₄ haloalkyl, —CN, —F, —Cl, —Br, and —I; R₃ is selected from —C₁-C₄ alkyl, —C₁-C₄ haloakyl, —CN, —F, —Cl, and —I, and R₂₀ is independently selected from —C₁-C₂₀ alkyl, —C₁-C₂₀ alkenyl, —C₁-C₂₀ alkynyl, and —C₁-C₂₀ containing at least one double bond and at least one triple bond.

Compounds such as: 3-(6-Hydroxy-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-2-yl)-propionic acid methyl ester; 3-(6-Hydroxy-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chroman-2-yl)-propionic acid; 2,2,-Dimethyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-6-ol; 3-(6-Hydroxy-2-methyl-3,4,7,8,9,10-hexahydro-7,10-propano-2H-benzo[h]chromen-2-yl)-propionic acid methyl ester; 2-Methyl-2-[3-(thiazol-2-ylsulfanyl)-propyl]-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-6-ol; [3-(6-Hydroxy-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-2-yl)-propyl]-phosphonic acid dimethyl ester; [3-(6-Hydroxy-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-2-yl)-propyl]-phosphonic acid; 3-(6-Hydroxy-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-2-yl)-propionic acid methyl ester; 4-(6-Hydroxy-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-2-yl)-butane-1-sulfonic acid dimethylamide; 2-(3-Hydroxy-propyl)-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-6-ol; 2-(3-Chloro-propyl)-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-6-ol 2,2-Dimethyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-6-ol; -(2-Chloro-ethyl)-2-methyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-6-ol; 2-Methyl-2-thiazol-2-yl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-6-ol; 2,2-Dimethyl-3,4,7,8,9,10-hexahydro-7,10-ethano-2H-benzo[h]chromen-6-ol; 3-(6-Hydroxy-2-methyl-3,4,7,8,9,10-hexahydro-7,10-ethano-2H-benzo[h]chromen-2-yl)-propionic acid; 2-(3-Chloro-propyl)-2-methyl-3,4,7,8,9,10-hexahydro-7,10-ethano-2H-benzo[h]chromen-6-ol; 4-(6-Hydroxy-2,2-dimethyl-3,4,7,8,9,10-hexahydro-7,10-methano-2H-benzo[h]chromen-5-ylmethylene)-2-methyl-5-propyl-2,4-dihydro-pyrazol-3-one.

Compounds such as: 2,2,7,8-Tetramethyl-5-phenyl-chroman-6-ol; 4-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl)-benzoic acid methyl ester; 4-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl)-benzoic acid; 2,2,7,8-Tetramethyl-5-pyridin-4-yl-chroman-6-ol; 2,2,7,8-Tetramethyl-5-pyridin-3-yl-chroman-6-ol; 5-(4-Methanesulfonyl-phenyl)-2,2,7,8-tetramethyl-chroman-6-ol; 5-(4-Dimethylamino-phenyl)-2,2,7,8-tetramethyl-chroman-6-ol; 5-(4-Chloro-phenyl)-2,2,7,8-tetramethyl-chroman-6-ol; 4-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl)-benzenesulfonamide; 5-(4-Methoxy-phenyl)-2,2,7,8-tetramethyl-chroman-6-ol; (6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-ylmethyl)-1-hydroxyurea; 2,2,7,8-Tetramethyl-5-(3-nitro-phenyl)-chroman-6-ol; 2,2,7,8-Tetramethyl-5-(4-trifluoromethyl-phenyl)-chroman-6-ol; 5-(4-tert-Butyl-phenyl)-2,2,7,8-tetramethyl-chroman-6-ol; 2,2,7,8-Tetramethyl-5-(3,4,5-trimethoxy-phenyl)-chroman-6-ol; 4-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl)-benzonitrile; 5-(2,5-Dimethoxy-3,4-dimethyl-phenyl)-2,2,7,8-tetramethyl-chroman-6-ol; 5-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl)-benzene-1,2,3-triol; 5-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl)-2, 3-dimethyl-benzene-1,4-diol; 5-(2-Chloro-phenyl)-2,2,7,8-tetramethyl-chroman-6-ol; 5-Furan-2-yl-2,2,7,8-tetramethyl-chroman-6-ol; 5-Allylsulfanylmethyl-2,2,8-trimethyl-7-(3-methyl-butyl)-chroman-6-ol; 5-Cyclopentylsulfanylmethyl-2,2,7,8-tetramethyl-chroman-6-ol; 5-Hexylsulfanylmethyl-2,2,7,8-tetramethyl-chroman-6-ol; 5-Allylsulfanylmethyl-2,2,7,8-tetramethyl-chroman-6-ol; 5-(4,6-Dimethyl-pyrimidin-2-ysulfanylmethyl)-2,2,7,8-tetramethyl-chroman-6-ol; 1-[3-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl-methylsulfanyl)-2-methyl-propionyl]-pyrrolidine-2-carboxylic acid; 4-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-ylmethylene)-5-methyl-2-phenyl-2,4-dihydro-pyrazol-3-one; 4-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl-methylene)-3-phenyl-4H-isoxazol-5-one; 4-[4-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl-methylene)-3-methyl-5-oxo-4,5-dihydro-pyrazol-1-yl]-benzoic acid; 4-(6-Hydroxy-2,2,7,8-tetramethyl-chroman-5-yl-methylene)-2-methyl-5-propyl-2,4-dihydro-pyrazol-3-one; 5-Hydroxy-3-(6-hydroxy-2,2,7,8-tetramethyl-chroman-5-yl-methylene)-3H-benzofuran-2-one; 2,5,7,8-Tetramethyl-2-thiophen-2-yl-chroman-6-ol; 2-(2,5-Dimethyl-thiophen-3-yl)-2,5,7,8-tetramethy 1-chroman-6-ol; 2-(2,5-Dimethyl-thiophen-3-yl)-2,7,8-trimethyl-chroman-6-ol; 8-Chloro-2-(2,5-dimethyl-thiophen-3-yl)-2,5,7-trimethyl-chroman-6-ol; 5-Chloro-2,7,8-trimethyl-2-thiophen-2-yl-chroman-6-ol; 5-[3-(6-Methoxymethoxy-2,7,8-trimethyl-chroman-2-yl)-propylidene]-thiazolidine-2,4-dione; 5-[3-(6-Hydroxy-2,7,8-trimethyl-chroman-2-yl)-propylidene]-thiazolidine-2,4-dione; 3-[6-Hydroxy-2,7,8-trimethyl-2-(4,8,12-trimethyl-tridecyl)-chroman-5-yl-methylsulfanyl]-2-methyl-propionic acid; 2,7,8-Trimethyl-5-(5-methyl-1H-benzoimidazol-2-yl-sulfanylmethyl)-2-(4,8,12-trimethyl-tridecyl)-chroman-6-ol; 2-[6-Hydroxy-2,7,8-trimethyl-2-(4,8,12-trimethyl-tridecyl)-chroman-5-ylmethylsulfanyl]-ethanesulfonic acid; 5-(4,6-Dimethyl-pyrimidin-2-ylsulfanylmethyl)-2,7,8-trimethyl-2-(4,8,12-trimethyl-tridecyl)-chroman-6-ol; 4-[2-(4,8-Dimethyl-tridecyl)-6-hydroxy-2,7,8-trimethyl-chroman-5-ylmethylsulfanyl]-benzoic acid; 1-{3-[6-Hydroxy-2,7,8-trimethyl-2-(4,8,12-trimethyl-tridecyl)-chroman-5-ylmethylsulfanyl]-2-methyl-propionyl}-pyrrolidine-2-carboxylic acid; 2-(2,2-Dichloro-vinyl)-2,5,7,8-tetramethyl-chroman-6-ol; 2-(2,2-Dibromo-vinyl)-2,5,7,8-tetramethyl-chroman-6-ol; 5-(5-Chloro-3-methyl-pent-2-enyl)-2,2,7,8-tetramethyl-chroman-6-ol; 5-Chloro-2-(2,5-dimethyl-thiophen-3-yl)-2,7,8-trimethyl-chroman-6-ol; 2-(3-Chloro-propyl)-5,7-dimethyl-2-thiophen-2-yl-chroman-6-ol; 5-Chloro-2-(2,5-dimethyl-thiazol-4-yl)-2,7,8-trimethyl-chroman-6-ol; 5-Chloro-2-(2,5-dimethyl-thiazol-4-yl)-2,7,8-trimethyl-2H-chromen-6-ol; and 5-Chloro-2-(2,5-dimethyl-thiazol-4-yl)-2,7,8-trimethyl-chroman-6-ol.

Compounds such as: dimebolin (2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole), 8-chloro-2-methyl-5-(2-(6-methylpyridin-3-yl)ethyl)-2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole, mebhydroline (5-benzyl-2-methyl-2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole), 2,8-dimethyl-1,3,4,4a, 5,9b-hexahydro-1H-pyrido[4,3-b]indole, 8-fluoro-2-(3-(pyridin-3-yl)propyl)-2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole, and 8-methyl-1,3,4,4a, 5,9b-tetrahydro-1H-pyrido[4,3-b]indole.

Compounds such as: 2-(3-hydroxy-3-methylbutyl)-3,5-dimethyl-6-(4-(trifluoromethyl)phenyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-6-(4-methoxyphenyl)-3,5-dimethylcyclohexa-2,5-diene-1,4-dione; 4-(5-(3-hydroxy-3-methylbutyl)-2,4-dimethyl-3,6-dioxocyclohexa-1,4-dienyl)benzonitrile; 2-(3-hydroxy-3-methylbutyl)-3,5-dimethyl-6-(naphthalen-2-yl)cyclohexa-2,5-diene-1,4-dione; 2-(3,4-difluorophenyl)-6-(3-hydroxy-3-methylbutyl)-3,5-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(4-fluorophenyl)-6-(3-hydroxy-3-methylbutyl)-3,5-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(4-chlorophenyl)-6-(3-hydroxy-3-methylbutyl)-3,5-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(2,3-dihydrobenzofuran-2-yl)-6-(3-hydroxy-3-methylbutyl)-3,5-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-phenethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-phenylcyclohexa-2,5-diene-1,4-dione; 2-benzyl-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(3-phenylpropyl)cyclohexa-2,5-diene-1,4-dione; 2-(1-hydroxy-2-phenylethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-3-(4-methoxyphenyl)-5,6-dimethyl-cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(4-(trifluoromethyl)-phenyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(naphthalen-2-yl)cyclohexa-2,5-diene-1,4-dione; 2-(benzofuran-2-yl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(4-chlorophenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(4-ethylphenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(3-(trifluoromethyl)phenyl)-cyclohexa-2,5-diene-1,4-dione; 2-(4-tert-butylphenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-cyclohexa-2,5-diene-1,4-dione; 2-(4-fluorophenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-fluorophenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 4-(2-(3-hydroxy-3-methylbutyl)-4,5-dimethyl-3,6-dioxocyclohexa-1,4-dienyl)benzonitrile; 2-(3,4-difluorophenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-cyclohexa-2,5-diene-1,4-dione; 2-(2-fluorophenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-3-(3-methoxyphenyl)-5,6-dimethyl-cyclohexa-2,5-diene-1,4-dione; 2-(4-fluoro-2-methoxyphenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(benzo[d][1,3]dioxol-5-yl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(2,4-difluorophenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-3-(4-methoxyphenyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3,5-bis(trifluoromethyl)phenyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(4-chlorophenyl)-6-(3-hydroxy-3-methylbutyl)-3,5-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(thiazol-2-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(thiazol-5-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(pyridin-2-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(pyridazin-4-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(thiophen-2-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(thiophen-3-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; 2-(2-(furan-2-yl)ethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(2-(furan-3-yl)ethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(2-(1H-pyrazol-5-yl)ethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(2-(1H-pyrazol-4-yl)ethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(2-(1H-pyrazol-1-yl)ethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(2-(1H-imidazol-5-yl)ethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(2-(1H-imidazol-2-yl)ethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(oxazol-5-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(oxazol-2-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; 2-(3-hydroxy-3-methylbutyl)-5,6-dimethyl-3-(2-(oxazol-4-yl)ethyl)cyclohexa-2,5-diene-1,4-dione; and 2-(2-(1H-indol-3-yl)ethyl)-3-(3-hydroxy-3-methylbutyl)-5,6-dimethylcyclohexa-2,5-diene-1,4-dione.

Compounds such as:

wherein m is —C₁-C₂₀ alkyl, —C₁-C₂₀ alkenyl, —C₁-C₂₀ alkynyl, or —C₁-C₂₀ containing at least one double bond and at least one triple bond, and the counterion is a pharmaceutically acceptable anion.

Compounds such as: 3-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)propyl triphenylphosphonium salts; 4-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)butyl triphenylphosphonium salts; 5-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)pentyl triphenylphosphonium salts; 6-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)hexyl triphenylphosphonium salts; 7-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)heptyl triphenylphosphonium salts; 8-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)octyl triphenylphosphonium salts; 9-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)nonyl triphenylphosphonium salts; 10-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)decyl triphenylphosphonium salts; 11-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)undecyl triphenylphosphonium salts; 12-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)dodecyl triphenylphosphonium salts; 13-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)propyldecyl triphenylphosphonium salts; 14-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)butyldecyl triphenylphosphonium salts; 15-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)pentadecyl triphenylphosphonium salts; 16-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)hexadecyl triphenylphosphonium salts; 17-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)heptadecyl triphenylphosphonium salts; 18-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)octadecyl triphenylphosphonium salts; 19-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)nonadecyl triphenylphosphonium salts; 20-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cyclohexadien-1-yl)icosyl triphenylphosphonium salts; 3-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)propyl triphenylphosphonium salts; 4-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)butyl triphenylphosphonium salts; 5-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)pentyl triphenylphosphonium salts; 6-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)hexyl triphenylphosphonium salts; 7-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)heptyl triphenylphosphonium salts; 8-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)octyl triphenylphosphonium salts; 9-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)nonyl triphenylphosphonium salts; 10-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)decyl triphenylphosphonium salts; 11-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)undecyl triphenylphosphonium salts; 12-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)dodecyl triphenylphosphonium salts; 13-(4,5-dimethoxy-2-methyl-3,6-dihydroxybenzyl)propyldecyl triphenylphosphonium salts; 14-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)butyldecyl triphenylphosphonium salts; 15-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)pentadecyl triphenylphosphonium salts; 16-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)hexadecyl triphenylphosphonium salts; 17-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)heptadecyl triphenylphosphonium salts; 18-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)octadecyl triphenylphosphonium salts; 19-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)nonadecyl triphenylphosphonium salts; 20-(4,5-dimethoxy-2-methyl-3,6-dihydroxyphenyl)icosyl triphenylphosphonium salts; wherein the counterion of the salt is a pharmaceutically acceptable anion such as bromide, methanesulfonate ethanesulfonate, propanesulfonate, benzenesulfonate, p-toluenesulfonate, or 2-naphthylene sulfonate.

Additionally, it is contemplated that co-administration of antioxidants could take the form of consuming foods known to have increased levels of beneficial antioxidants. Such foods include both regular foods and “superfoods” which contain antioxidants. These foods include fruits, vegetables, and other foodstuffs such as strawberries, blackcurrants, blackberries, oranges, blueberries, pomegranates, tea, coffee, olive oil, chocolate, cinnamon, herbs, red wine, grain cereals, eggs, meat, legumes, nuts, spinach, turnip, rhubarb, cocao beans, maize, beans, cabbage, and the like.

Delivery and Additional Formulations:

It is well known that triglycerides are the main constituents of vegetable oils and animal fats. It is also known that a triglyceride is an ester compound derived from glycerol and three fatty acids. Triglycerides are metabolized by enzymes such as lipases which hydrolyze ester bonds and release fatty acids and glycerol. Indeed, this metabolism releases fatty acids which can then be taken upon by cells via a fatty acid transporter protein. It is contemplated that PUFAs and PUFA mimetics that are useful in treating various diseases may be incorporated into fats such as triglycerides, diglycerides, and/or monoglycerides for administration to a patient.

The delivery of the PUFAs, PUFA mimetics, PUFA pro-drugs, and triglycerides containing PUFAs and/or PUFA mimetics could be through a modified diet. Alternatively, the PUFAs, PUFA mimetics, PUFA pro-drugs, and triglycerides containing PUFAs and/or PUFA mimetics can be administered as foods or food supplements, on their own or as complexes with ‘carriers’, including, but not limited to, complexes with albumin.

Other methods of delivering the reinforced PUFAs or their precursors, such as methods typically used for drug delivery and medication delivery, can also be employed. These methods include, but are not limited to, peroral delivery, topical delivery, transmucosal delivery such as nasal delivery, nasal delivery through cribriform plate, intravenous delivery, subcutaneous delivery, inhalation, or through eye drops.

Targeted delivery methods and sustained release methods, including, but not limited to, the liposome delivery method, can also be employed.

In some embodiments, the isotopically modified compounds described herein may be administered over a course of time in which the cells and tissues of the subject will contain increasing levels of isotopically modified compounds over the course of time in which the compounds are administered.

Compositions containing the active ingredient may be in a form suitable for oral use, for example, as tablets, troches, lozenges, aqueous or oily suspensions, oil-in-water emulsions, dispersible powders or granules, emulsions, hard or soft capsules, or syrups or elixirs. Such compositions may contain excipients such as bulking agents, solubilization agents, taste masking agents, stabilizers, coloring agents, preservatives and other agents known to those ordinarily skilled in the art of pharmaceutical formulation. In addition, oral forms may include food or food supplements containing the compounds described herein. In some embodiments supplements can be tailor-made so that one type of PUFA, such as omega-3 or omega-6 fatty acids can be added to food or used as a supplement depending on the dominant fat that the food or the subject's diet contains. Moreover, compositions can be tailor-made depending on the disease to be treated. For example, an LDL related condition may require more D-linoleic acid because cardiolipin, which is made of linoleic acid, is oxidized. In other embodiments, such as retinal disease and neurological/CNS conditions may require more omega-3 fatty acids such as D-linolenic acid, because D-omega-3 fatty acids are more relevant for treating these diseases. In some aspects, when the disease is associated with HNE, then D-omega-6 fatty acids should be prescribed, whereas for HHE, D-omega-3 fatty acids should be prescribed.

Compositions may also be suitable for delivery by topical application, as a spray, cream, ointment, lotion, or as a component or additive to a patch, bandage or wound dressing. In addition the compound can be delivered to the site of the disease by mechanical means, or targeted to the site of the disease through the use of systemic targeting technologies such as liposomes (with or without chemical modification that provides them with affinity for the diseased tissue), antibodies, aptamers, lectins, or chemical ligands such as albumin, with affinity for aspects of the diseased tissue that are less abundant or not present on normal tissue. In some aspects, topical application of cosmetics may include the use of a carrier which is an isotopically modified compound or mimetic described herein for delivering through skin such as by a patch. Eye disorders may be treated with eyedrops.

A pharmaceutical composition may also be in a form suitable for administration by injection. Such compositions may be in the form of a solution, a suspension or an emulsion. Such compositions may include stabilizing agents, antimicrobial agents or other materials to improve the function of the medicament. Some aspects of the invention also encompass dry or desiccated forms of the compounds which can readily be formed or reconstituted into a solution suspension or emulsion suitable for administration by injection, or for oral or topical use. Delivery by injection may be suitable for systemic delivery, and also local delivery such as injection into the eye for treating disorders relating to the eye.

Dosages

In some embodiments, compounds are dosed at about 0.01 mg/kg to about 1000 mg/kg, about 0.1 mg/kg to about 100 mg/kg, and/or about 1 mg/kg to about 10 mg/kg. In other embodiments, compounds are dosed at about: 0.01, 0.1, 1.0, 5.0, 10, 25, 50, 75, 100, 150, 200, 300, 400, 500, and/or 1000 mg/kg.

EXAMPLES

Experimental: MALDI-TOF mass-spectra were recorded on a PE-ABI Voyager Elite delayed extraction instrument. Spectra were acquired with an accelerating voltage of 25 KV and 100 ms delay in the positive ion mode. Unless otherwise specified, the 1H NMR spectra were recorded on a Varian Gemini 200 MHz spectrometer. HPLC was carried out on a Waters system. Chemicals were from Sigma-Aldrich Chemical Company (USA), Avocado research chemicals (UK), Lancaster Synthesis Ltd (UK), and Acros Organics (Fisher Scientific, UK). Silica gel, TLC plates and solvents were from BDH/Merck. IR spectra were recorded with Vertex 70 spectrometer. ¹H and ¹³C NMR spectra were obtained with a Bruker AC 400 instrument at 400 and 100 MHz respectively, in CDCl₃ (TMS at δ=0.00 or CHCl₃ at δ=7.26 for ¹H and CHCl₃ at δ=77.0 for ¹³C as an internal standard).

One of ordinary skill in the art will recognize that the below described syntheses can be readily modified to prepare additional oxidation-resistant compounds. For example, one will recognize the ester of one type of stabilized compound can be cleaved to afford the corresponding carboxylic acid. Likewise, carboxylic acids can be readily converted into additional derivatives, such as esters. Additionally, one will appreciate that by varying the identity of the isotopically labeled starting materials, isotopic variants of the below described compounds may be prepared. In the below described syntheses, paraformaldehyde-d₂ is used as an isotopically labeled starting material. One will readily appreciate that the same synthetic transformations can be used with paraformaldehyde-d₁, formaldehyde-d₁, paraformaldehyde-d₂, formaldehyde-d₂, and carbon-13 labeled variants of the aforementioned compounds. Formaldehyde-d₁ is a well-characterized compound and is readily available from known sources such as formic acid-d₁, formic acid-d₂, and/or dichloromethane-d₁ using generally known and understood synthetic transformations. Furthermore, radioactive analogues of the compounds described herein can be prepared using tritium-containing starting materials. These compounds would be useful for determining incorporation in the cells and tissues of animals.

Example 1. Synthesis of 11,11-D2-linoleic acid

1,1-Dideutero-oct-2-yn-1-ol (2) To a solution of ethylmagnesium bromide prepared from bromoethane (100 ml), 1,2-dibromoethane (1 ml) and magnesium turnings (31.2 g) in dry THF (800 ml), heptyn-1 ((1); 170 ml) was added dropwise over 30-60 min under argon. The reaction mixture was stirred for 1 h, and then deuteroparaform (30 g) was carefully added in one portion. The reaction mixture was gently refluxed for 2 h, chilled to −10° C., and then 5-7 ml of water was slowly added. The mixture was poured into 0.5 kg slurry of crushed ice and 40 ml concentrated sulphuric acid and washed with 0.5 L of hexane. The organic phase was separated, and the remaining aqueous phase was extracted with 5:1 hexane:ethyl acetate (3×300 ml). The combined organic fraction was washed with sat. NaCl (1×50 ml), sat. NaHCO₃, (1×50 ml), and dried over Na₂SO₄. The solvent was evaporated in vacuo to yield 119.3 g (99%) of colourless oil which was used without further purification. HRMS, m/z calculated for C₈H₁₂D₂O: 128.1168; found: 128.1173. ¹H NMR (CDCl₃, δ): 2.18 (t, J=7.0, 2H), 1.57 (s, 1H), 1.47 (q, J=7.0 Hz, 2H), 1.31 (m, 4H), 0.87 (t, J=7.0 Hz, 3H).

1,1-Dideutero-1-bromo-oct-2-yne (3) To a solution of (2) (3.48 g; 27.2 mmol) and pyridine (19 ml) in dry diethyl ether (300 ml), 36 ml of PBr₃ in 35 ml diethyl ether was added dropwise with stirring over 30 min at −15° C. under argon. The reaction mixture was allowed to gradually warm up to r.t. and then refluxed 3 h with stirring and 1 h without stirring. The reaction mixture was then cooled down to −10° C. and 500 ml of cold water was added. When the residue dissolved, saturated NaCl (250 ml) and hexane (250 ml) were added, and the organic layer was separated. The aqueous fraction was washed with hexane (2×100 ml), and the combined organic fractions were washed with NaCl (2×100 ml) and dried over Na₂SO₄ in presence of traces of hydroquinone and triethylamine. The solvent was removed by distillation at atmospheric pressure followed by rotary evaporation. The residue was fractionated by vacuum distillation (3 mm Hg) to give 147.4 g (82% counting per deutero-paraform) of pale yellow oil. B.p. 75° C. HRMS, m/z calculated for C₈H₁₁D₂Br: 190.0324; found: 189.0301, 191.0321. ¹H NMR (CDCl₃, δ): 2.23 (t, J=7.0 Hz, 2H, CH₂), 1.50 (m, 2H, CH₂), 1.33 (m, 4H, CH₂), 0.89 (t, J=6.9 Hz, 3H, CH₃),

11,11-Dideutero-octadeca-9,12-diynoic acid methyl ester (5) CuI (133 g) was quickly added to 400 ml of DMF (freshly distilled over CaH₂), followed by dry NaI (106 g), K₂CO₃ (143 g). Dec-9-ynoic acid methyl ester ((4); 65 g) was then added in one portion, followed by bromide (3) (67 g). Additional 250 ml of DMF was used to rinse the reagents off the flask walls into the bulk of reaction mixture, which was then stirred for 12 h. 500 ml of saturated aqueous NH₄Cl was then added with stirring, followed in a few minutes by saturated aqueous NaCl and then by a 5:1 mixture of hexane:EtOAc (300 ml). The mixture was further stirred for 15 min and then filtered through a fine mesh Schott glass filter. The residue was washed with hexane:EtOAc mix several times. The organic fraction was separated, and the aqueous phase was additionally extracted (3×200 ml). The combined organic fraction was dried (Na₂SO₄), traces of hydroquinone and diphenylamine were added, and the solvent was evaporated in vacuo. The residue was immediately distilled at 1 mm Hg, to give 79 g (77%) of a 165-175° C. boiling fraction. HRMS, m % z calculated for C₁₉H₂₈D₂O₂: 292.2369; found: 292.2365.

¹H NMR (CDCl₃, δ): 3.67 (s, 3H, OCH₃), 2.3 (t, J=7.5 Hz, 2H, CH₂), 2.14 (t, J=7.0 Hz, 4H, CH₂), 1.63 (m, 2H, CH₂), 1.47 (m, 4H, CH₂), 1.3 (m, 10H, CH₂), 0.88 (t, J=7.0 Hz, 3H, CH₃).

11,11-Dideutero-cis,cis-octadeca-9,12-dienoic acid methyl ester (6) A suspension of nickel acetate tetrahydrate (31.5 g) in 96% EtOH (400 ml) was heated with stirring to approx. 50-60° C. until the salt dissolved. The flask was flushed with hydrogen, and then 130 ml of NaBH₄ solution, (prepared by a 15 min stirring of NaBH₄ suspension (7.2 g) in EtOH (170 ml) followed by filtering) was added dropwise over 20-30 min with stirring. In 15-20 min ethylenediamine (39 ml) was added in one portion, followed in 5 min by an addition of (5) (75 g) in EtOH (200 ml). The reaction mixture was very vigorously stirred under hydrogen (1 atm). The absorption of hydrogen stopped in about 2 h. To the reaction mixture, 900 ml of hexane and 55 ml of ice cold AcOH were added, followed by water (15 ml). Hexane (400 ml) was added, and the mixture was allowed to separate. Aqueous fractions were extracted by 5:1 mix of hexane:EtOAc. The completion of extraction was monitored by TLC. The combined organic phase was washed with diluted solution of H₂SO₄, followed by saturated NaHCO₃ and saturated NaCl, and then dried over Na₂SO₄. The solvent was removed at reduced pressure. Silica gel (Silica gel 60, Merck; 162 g) was added to a solution of silver nitrate (43 g) in anhydrous MeCN (360 ml), and the solvent removed on a rotavap. The obtained impregnated silica gel was dried for 3 h at 50° C. (aspiration pump) and then 8 h on an oil pump. 30 g of this silica was used per gram of product. The reaction mixture was dissolved in a small volume of hexane and applied to the silver-modified silica gel, and pre-washed with a 1-3% gradient of EtOAc. When the non-polar contaminants were washed off (control by TLC), the product was eluted with 10% EtOAc and the solvent evaporated in vacuo to give 52 g of the title ester (6) as a colourless liquid. HRMS, m/z calculated for C₁₉H₃₂D₂O₂: 296.2682; found: 296.2676. IR (CCl₄): {tilde over (v)}=1740 cm⁻¹. ¹H NMR (CDCl₃, δ): 5.32 (m, 4H), 3.66 (s, 3H, OCH₃), 2.29 (t, J=7.5 Hz, 2H, CH₂), 2.02 (m, 4H, CH₂), 1.60 (m, 2H, CH₂), 1.30 (m, 14H, CH₂), 0.88 (t, J=7.0 Hz, 3H, CH₃).

11,11-Dideutero-cis,cis-octadeca-9,12-dienoic acid (7) A solution of KOH (46 g) in water (115 ml) was added to a solution of ester (6) (46 g) in MeOH (60 ml). The reaction mixture was stirred at 40-50° C. for 2 h (control by TLC) and then diluted with 200 ml of water. Two thirds of the solvent were removed (rotavap). Diluted sulphuric acid was added to the residue to pH 2, followed by diethyl ether with a little pentane. The organic layer was separated and the aqueous layer washed with diethyl ether with a little pentane. The combined organic fractions were washed with saturated aqueous NaCl and then dried over Na₂SO₄. The solvent was evaporated to give 43 g of (7) (99%). IR (CCl₄): {tilde over (v)}=1741, 1711 cm⁻¹.

Example 2. Synthesis of 11,11,14,14-D4-linolenic acid

1,1-Dideutero-pent-2-yn-1-ol (9) But-1-yne (8) was slowly bubbled through a solution of ethylmagnesium bromide prepared from bromoethane (100 ml) and magnesium turnings (31.3 g) in dry THF (800 ml) on a bath (−5° C.). Every now and then the bubbling was stopped and the cylinder with but-1-yne was weighed to measure the rate of consumption. The supply of alkyne was stopped shortly after a voluminous precipitate formed (the measured mass of alkyne consumed was 125 g). The reaction mixture was warmed up to r.t. over 30 min, and then stirred for 15 min. The mixture was then heated up to 30° C., at which point the precipitate dissolved, and then stirred at r.t. for another 30 min. Deuteroparaform (28 g) was added in one portion and the mixture was refluxed for 3 h, forming a clear solution. It was cooled down to r.t. and poured into a mixture of crushed ice (800 g) and 50 ml conc. H₂SO₄. Hexane (400 ml) was added and the organic layer was separated. The aqueous phase was saturated with NaCl and extracted with a 4:1 mixture of hexane:EtOAc (1 L). The completion of extraction process was monitored by TLC. The combined organic phases were washed with saturated NaCl, NaHCO₃ and again NaCl, and dried over Na₂SO₄. The solvent was removed by distillation at the atmospheric pressure (max vapour temperature 105° C.). The residue (70.5 g; 94%) was used without further purification. HRMS, m/z calculated for C₅H₆D₂O: 86.0699; found: 86.0751. ¹H NMR (CDCl₃, δ): 2.21 (q, J=7.5 Hz, 2H, CH₂), 1.93 (br s, 1H, OH), 1.12 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 87.7, 77.6, 13.7, 12.3 (signal of CD₂ is absent).

1,1-Dideutero-1-bromo-pent-2-yne (10) To a solution of (9) (70.5 g) and pyridine (16.5 ml) in dry diethyl ether (280 ml), 32.3 ml of PBr₃ in 50 ml diethyl ether was added dropwise with stirring over 30 min at −10° C. under argon. The reaction mixture was allowed to gradually warm up to r.t. over 1 h. A small amount of hydroquinone was added, and the mixture was then refluxed for 4.5 h. The reaction mixture was then cooled down to −10° C. and 350 ml of cold water was added. When the residue dissolved, saturated NaCl (350 ml) and hexane (300 ml) were added, and the organic layer was separated. The aqueous fraction was washed with diethyl ether (2×150 ml), and the combined organic fractions were washed with NaCl (2×50 ml) and dried over Na₂SO₄ in presence of traces of hydroquinone and triethylamine. The solvent was removed at atmospheric pressure, and then the 147-155° C. boiling fraction was distilled off. Alternatively, upon reaching 100° C., the distillation at atmospheric pressure was stopped and the product distilled off at 77-84° C. (25 mm Hg). Yield: 107 g of clear liquid. HRMS, m/z calculated for C₅H₅D₂Br: 147.9855; found: 146.9814, 148.9835. IR (CCl₄): {tilde over (v)}=2251 cm⁻¹. ¹H NMR (CDCl₃, δ): 2.23 (q, J=7.5 Hz, 2H, CH₂), 1.11 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 89.3, 74.5, 13.4, 12.6 (signal of CD₂ is absent).

1,1,4,4-Tetradeutero-octa-2,5-diyn-1-ol (12) Ethylmagnesium bromide, prepared from ethyl bromide (53 ml) and magnesium turnings (15.8 g) in 400 ml of dry THF, was added in small portions to 350 ml of dry THF, simultaneously with acetylene bubbling through this mixture (at approx. 25 L/h rate) with vigorous stirring. The Grignard reagent solution was fed to the mixture at approx. 10 ml per 2-5 min. When all ethylmagnesium bromide was added (after approx. 2.5 h), acetylene was bubbled through the system for another 15 min. Deuteroparaform (17.3 g) and CuCl (0.2 g) were added under argon, and the reaction mixture was refluxed without stirring for 2.5 h, until deuteroparaform dissolved, to yield a solution of (11). Ethylmagnesium bromide solution, prepared from 14.8 g magnesium and 50 ml ethyl bromide in 250 ml of dry THF, was added dropwise to the reaction mixture over 20 min. When the gas emanation ceased, a condenser was attached and 250 ml of solvent were distilled off. The reaction mixture was then cooled to 30° C., and CuCl (1.4 g) was added followed by a dropwise addition, over 15 min, of bromide (10) (69 g). The reaction mixture was then refluxed for 5 h, cooled slightly (a precipitate will form if cooling is too fast), and poured into a slurry of crushed ice (1-1.2 kg) and 40 ml concentrated H₂SO₄. The mixture was washed with hexane (600 ml). The organic fraction was separated, and the aqueous fraction was additionally extracted with 5:1 hexane:EtOAc (2×400 ml). The combined organic fraction was washed, with saturated NaCl, followed by saturated NaHCO₃ and NaCl. The bulk of the solvent was removed at atmospheric pressure in presence of traces of hydroquinone and triethylamine. The residue was flushed through 100 ml of silica gel (eluent: 7:1 hexane:EtOAc). The bulk of the solvent was removed at the atmospheric pressure, and the remainder on a rotavap. 49.5 g (85%) of the title compound obtained was used without further purification. HRMS, m/z calculated for C₈H₆D₄O: 126.0979; found: 126.0899. IR(CCl₄): {tilde over (v)}=3622 cm⁻¹. ¹H NMR (CDCl₃, δ): 2.16 (q, J=7.5 Hz, 2H, CH₂), 1.85 (br s, 1H, OH), 1.11 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 82.3, 80.4, 78.3, 72.6, 13.7, 12.2

1,1,4,4-Tetradeutero-1-bromo-octa-2,5-diyne (13) was synthesized as described for bromide (3); 2 ml of pyridine, 14 ml PBr₃ and 250 ml of diethyl ether was used for 54.2 g of alcohol (12). The product was purified by distillation at 4 mm Hg. Yield: 53 g (65%) of (13); b.p. 100-110° C. HRMS, m/z calculated for C₈H₅D₄Br: 188.0135; found: 187.0136, 189.0143. IR (CCl₄): {tilde over (v)}=2255 cm⁻¹. H NMR (CDCl₃, δ): 2.13 (q, J=7.5 Hz, 2H, CH₂); 1.07 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 82.5, 81.8, 75.0, 72.0, 13.6, 12.2.

11,11,14,14-Tetradeutero-octadeca-8,12,15-triynoic acid methyl ester (15) was synthesized in a way similar to that described for 11,11-dideutero-octadeca-9,12-diynoic acid methyl ester (5). CuI (97 g) was quickly added to 400 ml of DMF (freshly distilled over CaH₂), followed by dry NaI (77.5 g), K₂CO₃ (104.5 g). Dec-9-ynoic acid methyl ester ((14); 47.5 g) was then added in one portion, followed by bromide (13) (48.5 g). Additional 250 ml of DMF was used to rinse the reagents off the flask walls into the bulk of reaction mixture, which was then stirred for 12 h. 500 ml of saturated aqueous NH₄Cl was then added with stirring, followed in a few minutes by saturated aqueous NaCl (300 ml) followed by a 5:1 mixture of hexane:EtOAc (300 ml). The mixture was further stirred for 15 min and then filtered through a fine mesh Schott glass filter. The residue was washed with hexane:EtOAc mix several times. The organic fraction was separated, and the aqueous phase was additionally extracted (3×200 ml). The combined organic fraction was dried (Na₂SO₄), traces of hydroquinone and diphenylamine were added, and the solvent was evaporated in vacuo. The residue was immediately distilled at 1 mm Hg, to give 45.8 g (62%) of a 173-180° C. boiling fraction. An additional crystallisation was carried out as follows. The ester (15) was dissolved in hexane (500 ml) and cooled down to −50° C. The crystals formed were washed in cold hexane. The yield of this step is 80%. FIRMS, m/z calculated for C₁₉H₂₂D₄O₂: 290.2180; found: 290.2200. ¹H NMR (CDCl₃, δ): 3.66 (s, 3H, OCH₃), 2.29 (t, J=7.5 Hz, 2H, CH₂), 2.15 (m, 4H, CH₂), 1.61 (m, 2H, CH₂), 1.47 (m, 2H, CH₂), 1.30 (m, 6H, CH₂), 1.11 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 174.1, 82.0, 80.6, 74.7, 74.6, 73.7, 73.0, 51.3, 33.9, 28.9, 28.6, 28.52, 28.49, 24.8, 18.5, 13.7, 12.2.

11,11,14,14-Tetradeutero-cis,cis,cis-octadeca-8,12,15-trienoic acid methyl ester (16) was synthesized in a way similar to that described for 11,11-Dideutero-cis,cis-octadeca-9,12-dienoic acid methyl ester (‘6’). A suspension of nickel acetate tetrahydrate (42 g) in 96% EtOH (400 ml) was heated with stirring to approx. 50-60° C. until the salt dissolved. The flask was flushed with hydrogen, and then 130 ml of NaBH₄ solution, (prepared by a 15 min stirring of NaBH₄ suspension (7.2 g) in EtOH (170 ml) followed by filtering) was added dropwise over 20-30 min with stirring. In 15-20 min ethylenediamine (52 ml) was added in one portion, followed in 5 min by an addition of (15) (73 g) in EtOH (200 ml). The reaction mixture was very vigorously stirred under hydrogen (1 atm). The absorption of hydrogen stopped in about 2 h. To the reaction mixture, 900 ml of hexane and 55 ml of ice cold AcOH were added, followed by water (15 ml). Hexane (400 ml) was added, and the mixture was allowed to separate. Aqueous fractions were extracted by 5:1 mix of hexane:EtOAc. The completion of extraction was monitored by TLC. The combined organic phase was washed with diluted solution of H₂SO₄, followed by saturated NaHCO₃ and saturated NaCl, and then dried over Na₂SO₄. The solvent was removed at reduced pressure. Silica gel for purification was prepared as described for (6). 30 g of this silica was used per gram of product. The reaction mixture was dissolved in a small volume of hexane and applied to the silver-modified silica gel, and pre-washed with a 1-5% gradient of EtOAc. When the non-polar contaminants were washed off (control by TLC), the product was eluted with 10% EtOAc and the solvent evaporated in vacuo to give 42 g of the title ester (16) as a colourless liquid. HRMS, m/z calculated for C₁₉H₂₈D₄O₂: 296.2649; found: 296.2652. IR (CCl₄): {tilde over (v)}=1740 cm⁻¹. ¹H NMR (CDCl₃, δ): 5.4 (m, 6H, CH-double bond), 3.68 (s, 3H, OCH₃), 2.33 (t, J=7.5 Hz, 2H, CH₂), 2.09 (m, 4H, CH₂), 1.62 (m, 2H, CH₂), 1.33 (m, 8H, CH₂), 0.97 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 174.1, 131.9, 130.2, 128.2, 128.1, 127.7, 126.9, 51.3, 34.0, 29.5, 29.04, 29.02, 27.1, 25.5, 24.9, 20.5, 14.2.

11,11,14,14-Tetradeutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (17) A solution of KOH (1.5 g, 27 mmol) in water (2.6 ml was added to a solution of ester (16) (1.00 g, 3.4 mmol) in MeOH (15 ml). The reaction mixture was stirred at 40-50° C. for 2 h (control by TLC) and then diluted with 20 ml of water. Two thirds of the solvent were removed (rotavap). Diluted sulfuric acid was added to the residue to pH 2, followed by diethyl ether with a little pentane (50 ml). The organic layer was separated and the aqueous layer washed with diethyl ether with a little pentane (3×30 ml). The combined organic fractions were washed with saturated aqueous NaCl and then dried over Na₂SO₄. The solvent was evaporated to give 0.95 g of (17) (100%). IR (CCl₄): {tilde over (v)}=1741, 1711 cm⁻¹.

Example 3. Synthesis of 14,14-D2-linolenic acid

4,4-Dideutero-octa-2,5-diyn-1-ol (19) To a solution of ethylmagnesium bromide, prepared from ethyl bromide (9.2 ml, 123.4 mmol) and magnesium turnings (2.74 g, 112.8 mmol) in 40 ml of dry THF, on an ice bath with stirring, propargyl alcohol (3.16 g, 56.4 mmol) in THF (5 ml) was added dropwise over 10-15 min. The reaction mixture was allowed to warm up to r.t. and stirred for another 2 h, with occasional warming to 40° C. To thus generated dianion, 0.13 g of CuCl was added, followed by slow (over 15 min) addition of bromide (10) (6.9 g) in THF (20 ml). The reaction mixture was then stirred for 1 h at r.t. and then refluxed for 5 h. The reaction mixture was then refluxed for 5 h, cooled slightly (a precipitate will form if cooling is too fast), and poured into a slurry of crushed ice and 2.5 ml concentrated H₂SO₄. The mixture was washed with hexane (600 ml). The organic fraction was separated, and the aqueous fraction was additionally extracted with 5:1 hexane:EtOAc. The combined organic fraction was washed, with saturated NaCl, followed by saturated NaHCO₃ and NaCl, and dried over Na2SO4. The bulk of the solvent was removed at atmospheric pressure in presence of traces of hydroquinone and triethylamine. The product was purified by CC (hexane:EtOAc=15:1) to give 3.45 g (59%) of the product 19. HRMS, m/z calculated for C₈H₈D₂O: 124.0855; found: 124.0849. IR (CC14): {tilde over (v)}=3622 cm−1. 1H NMR (CDCl3, δ): 4.21 (m, 2H, CH2), 2.4 (m, 1H, OH), 2.16 (q, J=7.5 Hz, 2H, CH2), 1.11 (t, J=7.5 Hz, 3H, CH3). 13C NMR (CDCl3, δ): 82.3, 80.4, 78.3, 72.6, 51.0, 13.7, 12.2.

4,4-Dideutero-1-bromo-octa-2,5-diyne (20) was synthesized as described for (3), except all solvent was removed on a rotavap. From 3.4 g (27 mmol) of (19), 3.9 g (75%) of the bromide (20) was obtained, which was used without further purification. HRMS, m/z calculated for C₈H₇D₂Br: 186.0011; found: 185.0019, 187.0012. IR (CCl₄): {tilde over (v)}=2255 cm⁻¹. H NMVJR (CDCl₃, δ): 3.88 (br s, 2H, CH₂), 2.13 (q, J=7.5 Hz, 2H, CH₂), 1.07 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 82.5, 81.8, 75.0, 72.0, 14.8, 13.6, 12.2.

14,14-Dideutero-octadeca-8,12,15-triynoic acid methyl ester (21) was synthesized as described for (5). The product obtained from 9.7 g CuI, 7.8 g NaI, 10.5 g K₂CO₃, 4.85 g of bromide (20), 4.75 g of methyl ester (14) and 40 ml of anhydrous DMF, was purified by CC (25:1 hexane:EtOAc) to give 4.5 g (60%) of the title compound. HRMS, m/z calculated for C₁₉H₂₄D₂O₂: 288.2056; found: 288.2046. ¹H NMR (CDCl₃, δ): 3.66 (s, 3H, OCH₃), 3.12 (m, 2H, CH₂), 2.29 (t, J=7.5 Hz, 2H, CH₂), 2.15 (m, 4H, CH₂), 1.61 (m, 2H, CH₂), 1.47 (m, 2H, CH₂), 1.30 (m, 6H, CH₂), 1.11 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 174.1, 82.0, 80.6, 74.7, 74.6, 73.7, 73.0, 51.3, 33.9, 28.9, 28.6, 28.52, 28.49, 24.8, 18.5, 13.7, 12.2, 9.7.

14,14-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid methyl ester (22) was synthesized as described for the linoleic acid derivative (6). For a reduction of 4.5 g of (21), 2.6 g of nickel acetate tetrahydrate and 3.2 ml ethylenediamine was used. The product was purified on AgNO₃-impregnated silica gel as described for (6). HRMS, m/z calculated for C₁₉H₃₀D₂O₂: 294.2526; found: 294.2529. IR (CCl₄): {tilde over (v)}=1740 cm⁻¹. ¹H NMR (CDCl₃, δ): 5.37 (m, 6H, CH-double bond), 3.68 (s, 3H, OCH₃), 2.82 (m, 2H, CH₂), 2.33 (t, J=7.5 Hz, 2H, CH₂), 2.09 (m, 4H, CH₂), 1.62 (m, 2H, CH₂), 1.33 (m, 8H, CH₂), 0.97 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 174.1, 131.9, 130.2, 128.2, 128.1, 127.7, 126.9, 51.3, 34.0, 29.5, 29.1, 29.04, 29.02, 27.1, 25.5, 24.9, 20.5, 14.2.

14,14-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (23) To a solution of (22) (1 g, 3.4 mmol) in MeOH (15 ml), a solution of KOH (1.5 g, 27 mmol) in water (2.6 ml) was added in one portion. The reaction mixture was then processed as described for (7) to yield 0.94 g (99%) of the title acid. IR (CCl₄): {tilde over (v)}=1741, 1711 cm⁻¹.

Example 4. Synthesis of 11,11-D2-linolenic acid

Pent-2-yn-1-ol (24) Butyn-1 ((8); 10.4 g) was bubbled through an ice-cold solution prepared from bromoethane (11.2 ml) and magnesium turnings (3.6 g) in THF (100 ml). The reaction mixture was allowed to warm up to r.t. and then stirred for 15 min. The mixture was then heated up to 30° C., at which point all precipitate dissolved. The heating was removed and the mixture stirred for another 30 min, and then paraform (3 g) was added in one portion. The reaction mixture was refluxed for 3 h (all paraform dissolved), then cooled to r.t., poured into a mixture of crushed ice (80 g) and 8 ml conc. H₂SO₄, and extracted with diethyl ether. The organic phase was washed with saturated NaHCO₃ and NaCl, and dried over Na₂SO₄. The solvent was removed on a rotavap, and the residue (7.56 g; 90%) was used without further purification. HRMS, m/z calculated for C₅H₈O: 84.0575; found: 84.0583.

1-Bromo-pent-2-yne (25) To a solution of (24) (11.7 g) and pyridine (2.66 ml) in dry diethyl ether (34 ml), 5.2 ml of PBr₃ in 5 ml diethyl ether was added dropwise with stirring over 30 min at −10° C. under argon. The reaction mixture was allowed to gradually warm up to r.t. over 1 h. A catalytic amount of hydroquinone was added, and the mixture was then refluxed for 4.5 h. The reaction mixture was then cooled down to −10° C. and 35 ml of cold water was added. When the residue dissolved, saturated NaCl (35 ml) and diethyl ether (30 ml) were added, and the organic layer was separated. The aqueous fraction was washed with diethyl ether (2×15 ml), and the combined organic fractions were washed with NaCl (2×400 ml) and dried over MgSO₄. The solvent was removed at atmospheric pressure, and then under reduced pressure (25 mm Hg), the 60-90° C. fraction was collected. Yield: 11.1 g (84%). HRMS, m/z calculated for C₅H₇Br: 145.9731; found: 144.9750, 146.9757.

1,1-Dideutero-octa-2,5-diyn-1-ol (26) was synthesized as described for (12) with 87% yield. HRMS, m/z calculated for C₈H₈D₂O: 124.0855; found: 124.0868. IR (CCl₄): {acute over (v)}=3622 cm⁻¹. ¹H NMR (CDCl₃, δ): 2.65 (m, 2H, CH₂), 2.4 (m, 1H, OH), 2.1 (q, 2H, CH₂), 1.09 (t, 3H, CH₃).

1,1-Dideutero-1-brono-octa-2,5-diyne (27) was synthesized as described for (3), except all solvent was removed on a rotavap. The product was purified by distillation at reduced pressure. Yield: 86% (b.p. 100-105° C. at 4 mm Hg). HRMS, m/z calculated for C₈H₇D₂Br: 186.0011; found: 184.9948, 187.9999. IR (CCl₄): {tilde over (v)}=2255 cm⁻¹. ¹H NMR (CDCl₃, δ): 2.66 (m, 2H, CH₂), 2.1 (q, 2H, CH₂), 1.09 (t, 3H, CH₃).

11,11-Dideutero-octadeca-8,12,15-triynoic acid methyl ester (28) was synthesized as described for (5). The product obtained from 7.1 g CuI, 5.66 g NaI, 7.65 g K₂CO₃, 3.55 g of bromide (27), 3.47 g of methyl ester (14) and 30 ml of anhydrous DMF, was purified by CC (25:1 hexane:EtOAc) to give 3.7 g of the title compound. HRMS, m/z calculated for C₁₉H₂₄D₂O₂: 288.2056; found: 288.2069. ¹H NMR (CDCl₃, δ): 3.7 (s, 3H, OCH₃), 3.15 (br. s, 2H, CH₂), 2.35 (m, 2H, CH₂), 2.17 (m, 4H, CH₂), 1.61 (m, 2H, CH₂), 1.48 (m, 2H, CH₂), 1.35 (m, 6H, CH₂), 1.11 (t, 3H, CH₃).

11,11-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid methyl ester (29) was synthesized as described for the linoleic acid derivative (6). For a reduction of 3.7 g of (28), 2.16 g of nickel acetate tetrahydrate and 2.62 ml ethylenediamine was used. The product was purified on AgNO₃-impregnated silica gel as described for (6) to give 1.5 g. HRMS, m/z calculated for C₁₉H₃₀D₂O₂: 294.2526; found: 294.2402. IR (CCl₄): {tilde over (v)}=1740 cm⁻¹. ¹H NMR (CDCl₃, δ): 5.37 (m, 6H, CH-double bond), 3.6 (s, 3H, OCH₃), 2.82 (m, 2H, CH₂), 2.33 (t, o=7.5 Hz, 2H, CH₂), 2.09 (m 4H, CH₂), 1.62 (m, 2H, CH₂), 1.33 (m, 8H, CH₂), 0.97 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 174.1, 131.9, 130.2, 128.2, 128.1, 127.7, 126.9, 51.3, 34.0, 29.5, 29.1, 29.04, 29.02, 27.1, 25.5, 24.9, 20.5, 14.2.

11,11-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (30) To a solution of (29) (1.5 g, 5.1 mmol) in MeOH (7.5 ml), a solution of KOH (1.5 g, 27 mmol) in water (3 ml) was added in one portion. The reaction mixture was then processed as described for (17) to yield 0.9 g of the title acid. IR (CCl₄): {tilde over (v)}=1741, 1711 cm¹. ¹H NMR (CDCl₃, δ): 11.2 (br s, 1H, COOH), 5.37 (m, 6H, CH-double bond), 2.83 (m, 2H, CH₂), 2.35 (t, J=7.5 Hz, 2H, CH₂), 2.06 (m 4H, CH₂), 1.63 (m, 2H, CH₂), 1.32 (m, 8H, CH₂), 0.97 (t, J=7.5 Hz, 3H, CH₃). ¹³C NMR (CDCl₃, δ): 180.4, 131.9, 130.2, 128.3, 128.1, 127.6, 127.1, 34.1, 29.5, 29.1, 29.03, 28.98, 27.2, 25.5, 24.6, 20.5, 14.2.

Example 5. Synthesis of 8,8-D₂-Linoleic Acid Methyl Ester

8-Hydroxyoctanoic acid (502). A solution of 8-bromocaprylic acid (501, 37.5 g, 168 mmol), anhydrous sodium acetate (60.0 g, 732 mmol) and sodium iodide (1.0 g, 6.7 mmol) in DMF (200 ml) was stirred at 110-120° C. for 8 h. The reaction mixture was cooled to r.t., a solution of potassium hydroxide (28 g, 0.5 mol) in water (150 ml), was added, and the mixture was stirred at 100° C. for another hour. The reaction mixture was cooled to r.t. and poured into slurry of ice and concentrated sulfuric acid (45 ml). The solution obtained was saturated with NaCl and extracted (9×150 ml) with a mixture of EtOAc and petroleum ether (1:1). Combined organic fractions were washed twice with saturated NaCl and dried over Na₂SO₄. The solvent was evaporated to give 26.5 g (98%) of the product which was used without further purification. A small amount of the product was further purified by CC on silica (eluent: petroleum ether:EtOAc=2:1) and characterized. ¹H NMR (400 MHz, CDCl₃) δ 1.27-1.39 (m, 6H), 1.50-1.68 (m, 4H), 2.32 (t, 2H, J=7.5 Hz), 3.62 (t, 2H, J=6.5 Hz), 6.87 (br. s., 2H).

Methyl 8-(tetrahydro-2H-pyran-2-yloxy)octanoate (503). 8-Hydroxyoctanoic acid (502; 26.3 g, 164 mmol) was dissolved in methanol (500 ml) containing acetyl chloride (3.5 ml). The reaction mixture was refluxed for 5 h and the solvent removed in vacuo. To the residue dissolved in CH₂Cl₂ (200 ml), 3,4-dihydro-2H-pyran (29 ml, 318 mmol) was added, and the reaction mixture was refluxed for 20 min. Upon addition of 5 ml of triethylamine, the solvent was removed in vacuo, and the residue was dissolved in petroleum ether (100 ml) and washed with water. The organic layer was flush-purified on a small silica column (silica, 100 ml; eluent: from petroleum ether to petroleum ether:EtOAc=20:1). The work-up yielded 38.2 g (90%) of the product which was used without further purification. A small amount of the product was further purified by CC on silica (eluent: petroleum ether:EtOAc=15:1) and characterized. JR (CCl₄): {tilde over (v)}=1741 cm⁻¹. ¹H NMR (400 MHz, CDCl₃) δ 1.20-1.36 (m, 6H), 1.40-1.82 (m, 10H), 2.23 (t, 2H, J=7.5 Hz), 3.30 (dt, 1H, J=9.5 Hz, 6.5 Hz), 3.39-3.46 (m, 1H), 3.59 (s, 3H), 3.65 (dt, 1H, J=9.5 Hz, 7.0 Hz), 3.76-3.83 (m, 1H), 4.47-4.52 (m, 1H).

[1,1-D₂]-8-(tetrahydro-2H-pyran-2-yloxy)octan-1-ol (504). To a stirred solution of ester (503) (37.5 g, 145 mmol) in diethyl ether (100 ml) in an ice bath, a suspension of LiAlD₄ (4.0 g, 95 mmol) in diethyl ether (300 ml) was added drop wise over 1 h. To the cold reaction mixture, water (4 ml), 15% NaOH (4 ml) and water (12 ml) were added with stirring. The precipitate was filtered and washed with ethyl ether. Evaporation in vacuo gave 33.5 g (99%) of the product. A small amount of the product was further purified by CC on silica (eluent: petroleum ether:EtOAc=10:1) and characterized. IR (CCl₄): {tilde over (v)}=3638, 3499 cm⁻¹. ¹H NMR (400 MHz, CDCl₃) δ 1.22-1.33 (m, 8H), 1.42-1.56 (m, 8H), 1.61-1.69 (m, 1H), 1.71-1.80 (m, 1H), 2.38 (br. s., 1H), 3.31 (dt, 1H, J=9.5 Hz, 6.5 Hz), 3.40-3.46 (m, 1H), 3.66 (dt, 1H, J=9.5 Hz, 7.0 Hz), 3.76-3.84 (m, 1H), 4.49-4.53 (m, 1H). ¹³C NMR (100 MHz, CDCl₃) δ 19.5, 25.3, 25.5, 26.0, 29.2, 29.3, 29.5, 30.6, 32.4, 62.1, 67.5, 98.7.

[1,1-D₂]-8-(tetrahydro-2H-pyran-2-yloxy)octyl methanesulfonate (505). To a solution of alcohol (504) (33.4 g, 144 mmol) and triethylamine (45 ml, 323 mmol) in diethyl ether (300 ml) at 0° C., a solution of MsCl (14.2 ml, 183 mmol) in diethyl ether (100 ml) was added drop wise over 1 h with stirring. The reaction mixture was warmed up to r.t. and treated with water. The organic phase, combined with washings (2×50 ml) of the aqueous phase with Et₂O, was washed twice with saturated NaCl, dried over Na₂SO₄, and decanted. This was flush-purified on a small silica column (silica, 100 ml; petroleum ether:EtOAc=10:1). The work-up yielded 43.7 g (98%) of methanesulfonate (505). IR (CCl₄): {tilde over (v)}=1739 cm⁻¹. ¹H NMR (400 MHz, CDCl₃) δ 1.26-1.41 (m, 8H), 1.44-1.59 (m, 6H), 1.63-1.84 (m, 4H), 2.97 (s, 3H), 3.32 (dt, 1H, J=9.5 Hz, 6.5 Hz), 3.42-3.50 (m, 1H), 3.69 (dt, 1H, J=9.5 Hz, 7.0 Hz) 3.78-3.86 (m, 1H), 4.52-4.56 (m, 1H). ¹³C NMR (100 MHz, CDCl₃) δ 19.6, 25.2, 25.4, 26.0, 28.7, 28.8, 29.1, 29.5, 30.7, 37.2, 62.3, 67.4, 98.8.

2-([8,8-D₂]-dec-9-yne-1-yloxy)tetrahydro-2H-pyran (506). Methanesulfonate (505) (43.5 g, 140 mmol) in DMSO (100 ml) was added dropwise with stirring over 1 h to a suspension of a ethylenediamine—lithium acetylenide complex (70 g, 0.76 mol) in DMSO (200 ml), and then the mixture was stirred for 90 min. Reaction mixture was poured on ice, extracted (Et₂O, 3×150 ml), dried over Na₂SO₄ and evaporated. This was flush-purified on a small silica column (silica, 100 ml; petroleum ether). Removal of solvent (rotavap) gave 25.3 g (75%) of the product. A small amount of the product was further purified by CC on silica (eluent: petroleum ether:EtOAc=25:1) and characterized. IR (CCl₄): {tilde over (v)}=3314 cm⁻¹. ¹H NMR (400 MHz, CDCl₃) δ 1.21-1.38 (m, 8H), 1.42-1.57 (m, 8H), 1.62-1.70 (m, 1H), 1.73-1.83 (m, 1H), 1.89 (s, 1H), 3.32 (d.t., 1H, J=9.5 Hz, 6.5 Hz), 3.42-3.50 (m, 1H), 3.68 (d.t., 1H, J=9.5 Hz, 7.0 Hz) 3.78-3.86 (m, 1H), 4.51-4.54 (m, 1H). ¹³C NMR (100 MHz, CDCl₃) δ 19.6, 25.4, 26.1, 28.1, 28.5, 28.9, 29.2, 29.6, 30.6, 30.7, 62.1, 67.5, 68.0, 98.7.

[8,8-D₂]-dec-9-yne-1-ol (507). Ether (506) (25 g, 104 mmol) was dissolved in methanol (300 ml) containing pyridinium para-toluenesulfonate (0.2 g). Reaction mixture was refluxed for 3 h, quenched with Et₃N (1 ml), the solvent removed in vacuo, the residue dissolved in petroleum ether and filtered through a small amount of silica gel. The solvent was evaporated to give 15.4 g (95%) of the product. A small amount of the product was further purified by CC on silica (eluent: petroleum ether:EtOAc=15:1) and characterized. IR (CCl₄): {tilde over (v)}=3638, 3508, 3314 cm⁻¹. ¹H NMR (400 MHz, CDCl₃) δ 1.22-1.40 (m, 8H), 1.42-1.56 (m, 4H), 1.91 (s, 1H), 2.29 (br. s., 1H), 3.59 (t, J=6.5 Hz, 2H). ¹³C NMR (100 MHz, CDCl₃) δ 25.6, 28.1, 28.5, 29.0, 29.2, 32.6, 62.8, 68.1, 84.6.

[8,8-D₂]-methyl dec-9-ynoate (508). To a solution of chromium trioxide (24 g, 0.24 mol) and concentrated sulfuric acid (21 ml) in water (100 ml) in a two-neck round bottom flask on water bath at 30° C. with stirring, a solution of alcohol (507) (15.5 g, 99 mmol) in acetone (150 ml) was added dropwise over 90 min. Upon addition, the reaction mixture was stirred for another 15 min, and the excess of oxidizer was quenched with isopropyl alcohol. The mixture was poured into cold water and extracted with diethyl ether (5×50 ml). Combined organic fractions were washed with saturated NaCl, dried over Na₂SO₄, filtered, and the solvent removed in vacuo. The residue was dissolved in methanol (200 ml) and upon addition of concentrated sulfuric acid (1 ml) refluxed for 90 min. The acid was quenched with triethylamine (6.5 ml, 47 mmol), the solvent removed in vacuo, and the residue purified by CC on silica (eluent: petroleum ether:EtOAc=50:1) to give 12.6 g (69% counting per alcohol (507)) of ester (508), and characterized. IR (CCl₄): {tilde over (v)}=3314, 1740 cm⁻¹. ¹H NMR (400 MHz, CDCl₃) δ 1.19-1.38 (m, 6H), 1.41-1.48 (m, 2H), 1.51-1.61 (m, 2H), 1.88 (s, 1H), 2.25 (t, J=7.5 Hz, 2H), 3.60 (s, 3H). ¹³C NMR (100 MHz, CDCl₃) δ 24.7, 28.0, 28.3, 28.6, 28.8, 33.9, 51.3, 68.1, 84.4, 174.0.

[8,8-D₂]-methyl octadeca-9,12-diynoate (510). To DMF (20 ml) were added with stirring CuI (3.9 g, 20 mmol), followed by NaI (3.1 g, 21 mmol), K₂CO₃ (4.2 g, 30 mmol), ester (508) (1.9 g, 10.3 mmol), and bromide (509) (2.04 g, 10.8 mmol, synthesized as described in [2]). The reaction mixture was stirred at r.t. for 12 h. Saturated aqueous ammonium chloride (20 ml) was added to the mixture, followed by saturated NaCl (15 ml). The precipitate and the aqueous phase were washed with petroleum ether. The combined organic fractions were washed with saturated sodium chloride, dried over Na₂SO₄ and evaporated in vacuo. The residue was purified by CC on silica (eluent: petroleum ether:EtOAc=50:1) to give 2.47 g (82%) of the product. ¹H NMR (400 MHz, CDCl₃) δ 0.86 (t, J=7.0 Hz, 3H), 1.22-1.36 (m, 10H), 1.40-1.50 (m, 4H), 1.55-1.64 (m, 2H), 2.09-2.15 (m, 2H), 2.28 (t, J=7.5 Hz, 2H), 3.09 (t, J=2.5 Hz, 2H), 3.64 (s, 3H). ¹³C NMR (100 MHz, CDCl₃) δ 9.6, 13.9, 18.6, 22.1, 24.8, 28.3, 28.4, 28.5, 28.7, 28.9, 31.0, 34.0, 51.4, 74.4, 74.5, 80.2, 80.4, 174.2.

[8,8-D₂]-octadeca-9,12-dienoate (511). A suspension of finely ground Ni(Ac)₂×4H₂O (0.8 g, 3.2 mmol) in 96% ethanol (25 ml) was heated with stirring to 50-60° C. until the salt was fully dissolved. The system was flushed with hydrogen, and then a solution of NaBH₄ (3.4 ml; obtained by 15 min stirring of NaBH₄ suspension (0.53 g, 14 mmol) in ethanol (12 ml) followed by filtering through a fine filter) was added over 10 min. Evolvement of hydrogen was observed. In 15-20 min, ethylenediamine (1.65 ml, 25 mmol) was added to the reaction mixture in one portion with stirring, followed by the solution of (510) (2.4 g, 8.2 mmol) in ethanol (10 ml). The reaction mixture was vigorously stirred under hydrogen until there was no further absorption of hydrogen, and then treated with acetic acid (2.3 ml), water (10 ml), and extracted with petroleum ether:EtOAc (5:1). Combined organic fractions were washed with 10% sulfuric acid (10 ml), then with saturated sodium chloride, dried over Na₂SO₄, and the solvent was removed in vacuo. The residue was purified by CC on silica (eluent: petroleum ether:EtOAc=50:1) to give 2.33 g (96%) of the product. The product was then purified again by CC on silica impregnated with 20% AgNO₃ (eluent: petroleum ether to petroleum ether:EtOAc=2:1). 1.75 g (72%) of the product was obtained (97% purity by GC). ¹H NMR (400 MHz, CDCl₃) δ 0.88 (t, J=7.0 Hz, 3H), 1.20-1.40 (m, 14H), 1.55-1.66 (m, 2H), 1.97-2.09 (m, 2H), 2.29 (t, J=7.5 Hz, 2H), 2.72-2.79 (m, 2H), 3.66 (s, 3H), 5.28-5.41 (m, 4H). ¹³C NMR (100 MHz, CDCl₃) δ 14.0, 22.5, 24.9, 25.6, 27.2, 29.00, 29.08, 29.13, 29.3, 29.4, 31.5, 34.1, 51.4, 127.9, 128.0, 129.9, 130.2, 174.2.

Example 6. Synthesis of 11-D-Linoleic Acid

oct-2-yn-1-ol (13). To a solution of oct-2-ynal [See Corey, E. J.; Schmidt, G. Tetrahedron Lett. 1979, 20, 399; Meyer, M. P.; Klinman, J. P. Tetrahedron Lett. 2008, 49, 3600]((612); 1.00 g, 8.1 mmol)) in ethanol (15 ml) cooled to 0° C., 0.11 g (2.6 mmol) of NaBD₄ was added in portions over 5 min. Upon addition, the solution was stirred for another 30 min, diluted with water (100 ml), and then extracted with Et₂O (4×20 ml). The combined organic fractions were washed with saturated NaCl, dried (Na₂SO₄), and the solvent was removed at reduced pressure. Alcohol 613 (0.85 g, 83%) was purified by column chromatography (silica gel, petroleum ether:EtOAc (15:1)). ¹H NMR (400 MHz, CDCl₃) δ 0.88 (t, J=7.0 Hz, 3H, CH₃), 1.32 (m, 4H, CH₂), 1.49 (quint, J=7.0 Hz, 2H, CH₂), 1.81 (br s, 1H, OH), 2.19 (td, J=7.0 Hz, 2.0 Hz, 2H, CH₂), 4.22 (m, 1H, CHD).

1-bromooct-2-yne (614) was synthesized as described in [See Hill, Sh.; Hirano, K.; Shmanai, V. V.; Marbois, B. N.; Vidovic, D.; Bekish, A. V.; Kay, B.; Tse, V.; Fine, J.; Clarke, C. F.; Shchepinov, M. S. Free Radic. Biol. Med., 2011, 50 (1), 130-138.]. ¹HNMR (400 MHz, CDCl₃) δ 0.89 (t, J=7.0 Hz, 3H, CH₃), 1.32 (m, 4H, CH₂), 1.50 (quint, J=7.0 Hz, 2H, CH₂), 2.22 (td, J=7.0 Hz, 2.0 Hz, 2H, CH₂), 3.91 (m, 1H, CHD).

[11⁻²H]-ethyl octadeca-9,12-diynoate (615), was synthesized as described [See Meyer, M. P.; Klinman, J. P. Tetrahedron Lett. 2008, 49, 3600; Hill, Sh.; Hirano, K.; Shmanai, V. V.; Marbois, B. N.; Vidovic, D.; Bekish, A. V.; Kay, B.; Tse, V.; Fine, J.; Clarke, C. F.; Shchepinov, M. S. Free Radic. Biol. Med., 2011, 50 (1), 130-138]. CuI (2 g, 10.5 mmol), NaI (1.58 g, 10.5 mmol), K₂CO₃ (2.1 g, 15 mmol), ethyl dec-9-ynoate (1.02 g, 5.2 mmol) and bromide 614 (1.03 g, 5.4 mmol) were added to DMF (10 ml) with stirring. The reaction mixture was stirred at RT for 12 h, then NH₄Cl (10 ml) and NaCl (8 ml) were added and the stirring continued for another 5 min. The precipitate was separated and washed with petroleum ether. Organic layers were separated, and the aqueous layer was extracted with petroleum ether. The combined organic fractions were washed with saturated NaCl, dried (Na₂SO₄), and the solvent was removed at reduced pressure. Column chromatography (silica gel, petroleum ether:EtOAc (15:1)) yielded 1.29 g (81%) of the product. ¹H NMR (400 MHz, CDCl₃) δ 0.89 (t, J=7.0 Hz, 3H, CH₃), 1.25 (t, J=7.0 Hz, 3H, CH₃CH₂O), 1.31 (m, 10H, CH₂), 1.49 (m, 4H, CH₂), 1.61 (m, 2H, CH₂), 2.15 (td, J=7.0 Hz, 2.0 Hz, 2H, CH₂ in propargylic position), 2.28 (t, J=7.5 Hz, 2H, CH₂COOEt), 3.10 (m, 1H, CHD), 4.12 (q, J=7.0 Hz, 2H, OCH₂CH₃). ¹³C NMR (100 MHz, CDCl₃) δ 9.6 (t, J=19.0 Hz), 13.9, 14.1, 18.56, 18.57, 22.1, 24.8, 28.4, 28.6, 28.7, 28.9, 28.9, 31.0, 34.2, 60.0, 74.3, 74.5, 80.2, 80.3, 173.7.

[11⁻² H]-linoleic acid (616) A suspension of triturated nickel acetate tetrahydrate (0.4 g, 1.6 mmol) in 96% ethanol (12 ml) was heated at 50-60° C. with stirring until the salt dissolved. The system was flushed with hydrogen, and then 1.7 ml of NaBH₄ (obtained by 15-min stirring of a NaBH₄ suspension (0.27 g, 14 mmol) in ethanol (6 ml) followed by filtering) was added over 10 min, with some gas bubbles evolving. In 15-20 min, ethylenediamine (0.8 ml, 12 mmol) was added in one portion with stirring, followed in 5 min by a solution of diyne 615 (1.2 g, 3.9 mmol) in ethanol (5 ml). The reaction mixture was stirred vigorously until there was no more absorption of hydrogen, and then treated with acetic acid (1.2 ml), water (10 ml) and extracted with a mixture of petroleum ether and EtOAc (5:1). The combined organic fractions were washed with 10% sulphuric acid (5 ml) and then with saturated NaCl, dried (Na₂SO₄), and the solvent was removed at reduced pressure. Column chromatography (silica gel, petroleum ether:EtOAc (50:1)) yielded 1.14 g (94%) of the product. The product was additionally purified [3] on a silver nitrate-impregnated silica (20% AgNO₃), with petroleum ether:EtOAc (2:1) as eluent to give 0.73 g (60%) of the linoleic acid ethyl ester (>96% purity by GC; GC-MS: MW 309 (GC-MS for a control non-deuterated linoleic acid ethyl ester: MW 308). ¹H NMR (400 MHz, CDCl₃) δ 0.89 (t, J=7.0 Hz, 3H, CH₃), 1.25 (t, J=7.0 Hz, 3H, CH₃CH₂O), 1.30 (m, 14H, CH₂), 1.61 (m, 2H, CH₂), 2.04 (m, 2H), 2.28 (t, J=7.5 Hz, 2H, CH₂COOEt), 2.74 (m, 1H, CHD), 4.12 (q, J=7.0 Hz, 2H, OCH₂CH₃), 5.34 (m, 4H, CH═CH). ¹³C NMR (100 MHz, CDCl₃) δ 14.1, 14.2, 22.6, 25.0, 25.3 (t, J=19.5 Hz), 27.17, 27.19, 29.08, 29.09, 29.14, 29.3, 29.6, 31.5, 34.4, 60.1, 127.8, 128.0, 130.0, 130.2, 173.9.

To obtain the free [11⁻²H]-linoleic acid (616), to the solution of the linoleic acid ethyl ester (0.704 g, 2.3 mmol) in ethanol (10 ml) a solution of KOH (0.4 g, 7.1 mmol) in water (0.8 ml) was added. The mixture was stirred at 50° C. for 10 min and then diluted with water (20 ml), treated with 10% solution of sulphuric acid (5 ml) and extracted with Et₂O (4×20 ml). The combined organic fractions were washed with saturated NaCl, dried over Na₂SO₄, and the solvent was removed at reduced pressure. The residue was flushed through a small volume of silica gel (2 ml; eluent: petroleum ether:EtOAc (2:1)) and the solvent removed in vacuo to yield 0.629 g (98%) of the indicated acid 616. ¹H NMR (400 MHz, CDCl₃) δ 0.88 (t, J=7.0 Hz, 3H, CH₃), 1.30 (m, 14H, CH₂), 1.60 (m, 2H, CH₂), 2.03 (m, 4H, CH₂), 2.33 (t, J=7.5 Hz, 2H, CH₂COOEt), 2.74 (m, 1H, CHD), 5.32 (m, 4H, CH═CH), 11.6 (br s, 1H, COOH). ¹³C NMR (100 MHz, CDCl₃) δ 14.1, 22.6, 24.6, 25.3 (t, J=19.0 Hz), 27.16, 27.18, 29.00, 29.05, 29.12, 29.3, 29.6, 31.5, 34.0, 127.8, 128.0, 130.0, 130.2, 180.1.

Example 7. Synthesis of [11-¹³C]-Linoleic Acid

[1-¹³C]-oct-2-yn-1-ol (717). The title compound has been synthesized according to the earlier described protocols (Hill, Sh.; Hirano, K.; Shmanai, V. V.; Marbois, B. N.; Vidovic, D.; Bekish, A. V.; Kay, B.; Tse, V.; Fine, J.; Clarke, C. F.; Shchepinov, M. S. Free Radic. Biol. Med., 2011, 50 (1), 130-138) using ¹³C-paraform, and used without further purification. ¹H NMR (CDCl₃, δ): 4.22 (A, J=148 Hz, 2H), 2.18 (td, J₁=7.0, J₂=1 Hz, 2H), 1.91 (br s, 1H), 1.47 (quint, J=7.0 Hz, 2H), 1.31 (m, 4H), 0.87 (t, J=7.0 Hz, 3H).

[1-¹³C]-1-bromooct-2-yne (718) was synthesized as described in (Hill, Sh.; Hirano, K.; Shmanai, V. V.; Marbois, B. N.; Vidovic, D.; Bekish, A. V.; Kay, B.; Tse, V.; Fine, J.; Clarke, C. F.; Shchepinov, M. S. Free Radic. Biol. Med., 2011, 50 (1), 130-138). Yield: 82% starting from ¹³C-paraform (per two steps). ¹H NMR (CDCl₃, δ): 3.93 (dt, J₁=158 Hz, J₂=2 Hz, 2.23 (m, 2H), 1.50 (m, 2H), 1.33 (m, 4H), 0.89 (t, J=7 Hz, 3H).

[11-¹³C]-ethyl octadeca-9,12-diynoate (719), was synthesized as previously described (See Meyer, M. P.; Klinman, J. P. Tetrahedron Lett. 2008, 49, 3600; Hill, Sh.; Hirano, K.; Shmanai, V. V.; Marbois, B. N.; Vidovic, D.; Bekish, A. V.; Kay, B.; Tse, V.; Fine, J.; Clarke, C. F.; Shchepinov, M. S. Free Radic. Biol. Med., 2011, 50 (1), 130-138). Yield: 93%. ¹H NMR (CDCl₃, δ): 4.10 (q, J=7 Hz, 2H), 3.1 (dm, J=134 Hz, 2H), 2.27 (t, J=7.5 Hz, 2H), 2.13 (m, 4H), 1.60 (m, 2H), 1.47 (m, 4H), 1.3 (m, 10H), 1.24 (t, J=7 Hz, 3H), 0.88 (t, J=7.0 Hz, 3H).

[11-¹³C]-linoleic acid ethyl ester (720) was synthesized as previously described (See Meyer, M. P.; Klinman, J. P. Tetrahedron Lett. 2008, 49, 3600; Hill, Sh.; Hirano, K.; Shmanai, V. V.; Marbois, B. N.; Vidovic, D.; Bekish, A. V.; Kay, B.; Tse, V.; Fine, J.; Clarke, C. F.; Shchepinov, M. S. Free Radic. Biol. Med., 2011, 50 (1), 130-138). Yield: 56%. ¹H NMR (CDCl₃, δ): 5.34 (m, 4H), 4.12 (q, J=7 Hz, 2H), 2.77 (dm, J=126 Hz, 2H), 2.28 (t, J=7.5 Hz, 2H), 2.04 (m, 4H), 1.61 (m, 2H), 1.30 (m, 14H), 1.25 (t, J=7 Hz, 3H), 0.88 (t, J=7.0 Hz, 3H).

[11-¹³C]-linoleic acid (721) was synthesized as previously described (See Meyer, M. P.; Klinman, J. P. Tetrahedron Lett. 2008, 49, 3600; Hill, Sh.; Hirano, K.; Shmanai, V. V.; Marbois, B. N.; Vidovic, D.; Bekish, A. V.; Kay, B.; Tse, V.; Fine, J.; Clarke, C. F.; Shchepinov, M. S. Free Radic. Biol. Med., 2011, 50 (1), 130-138); yield 98%. ¹H NMR (CDCl₃, 5): 10.5 (br s, 1H), 5.34 (m, 4H), 2.77 (dm, J=126 Hz), 2.33 (t, J=7.5 Hz, 2H), 2.03 (m, 4H), 1.60 (m, 2H), 1.30 (m, 14H), 0.88 (t, J=7.0 Hz, 3H).

Example 8. General Preparation of Esters A-D

General Procedure for Compound A. Thionyl chloride (2 equivalents) is slowly added to a solution of PUFA (1 equivalent) in CHCl₃. The reaction mixture is heated to reflux for 1 hr, then it is allowed to cool to room temperature and the solvent is evaporated under reduced pressure to afford the carboxylic acid chloride derivative of the PUFA. The carboxylic acid chloride derivative is then dissolved in anhydrous pyridine and the alcohol (1 equivalent) dissolved in pyridine is slowly added (Note that the order of addition is reversed when the alcohol is a polyalcohol). Upon complete addition, the reaction mixture is allowed to stir at room temperature for 24 hr. The solvent is then removed under reduced pressure and the crude product is purified by column chromatography to afford Compound A.

11,11-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (30); 14,14-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (23); 11,11,14,14-Tetradeutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (17); and 11,11-Dideutero-cis,cis-octadeca-9,12-dienoic acid (7) are each subjected to the above described procedure with the following alcohols: ethanol, glycerol, propylene glycol; glucose; 2-(2-ethoxyethoxy)ethanol; and estradiol to afford products corresponding to the general formula of Compound A.

General Procedure for Compound B. Thionyl chloride (2 equivalents) is slowly added to a solution of PUFA (1 equivalent) in CHCl₃. The reaction mixture is heated to reflux for 1 hr, then it is allowed to cool to room temperature and the solvent is evaporated under reduced pressure to afford the carboxylic acid chloride derivative of the PUFA. The carboxylic acid chloride derivative is then dissolved in anhydrous pyridine and the alcohol (Compound A, 1 equivalent) dissolved in pyridine is slowly added. Upon complete addition, the reaction mixture is allowed to stir at room temperature for 24 hr. The solvent is then removed under reduced pressure and the crude product is purified by column chromatography to afford Compound B.

The Compound A products that form from the condensation of 11,11-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (30); 14,14-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (23); 11,11,14,14-Tetradeutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (17); and 11,11-Dideutero-cis,cis-octadeca-9,12-dienoic acid (7) with glycerol, propylene glycol; glucose; and estradiol are treated according to the above-described general procedure with 11,11-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (30); 14,14-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (23); 11,11,14,14-Tetradeutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (17); and 11,11-Dideutero-cis,cis-octadeca-9,12-dienoic acid (7) as the PUFAs to afford products corresponding to the general formula of Compound B.

General Procedure for Compound C. Thionyl chloride (2 equivalents) is slowly added to a solution of PUFA (1 equivalent) in CHCl₃. The reaction mixture is heated to reflux for 1 hr, then it is allowed to cool to room temperature and the solvent is evaporated under reduced pressure to afford the carboxylic acid chloride derivative of the PUFA. The carboxylic acid chloride derivative is then dissolved in anhydrous pyridine and the alcohol (Compound B, 1 equivalent) dissolved in pyridine is slowly added. Upon complete addition, the reaction mixture is allowed to stir at room temperature for 24 hr. The solvent is then removed under reduced pressure and the crude product is purified by column chromatography to afford Compound C.

The Compound B products that form from the condensation of Compound A products with glycerol and glucose are treated according to the above-described general procedure with 11,11-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (30); 14,14-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (23); 11,11,14,14-Tetradeutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (17); and 11,11-Dideutero-cis,cis-octadeca-9,12-dienoic acid (7) as the PUFAs to afford products corresponding to the general formula of Compound C.

General Procedure for Compound D. Thionyl chloride (2 equivalents) is slowly added to a solution of PUFA (1 equivalent) in CHCl₃. The reaction mixture is heated to reflux for 1 hr, then it is allowed to cool to room temperature and the solvent is evaporated under reduced pressure to afford the carboxylic acid chloride derivative of the PUFA. The carboxylic acid chloride derivative (4 equivalents) is then dissolved in anhydrous pyridine and the alcohol (1 equivalent) dissolved in pyridine is slowly added. Upon complete addition, the reaction mixture is allowed to stir at room temperature for 24 hr. The solvent is then removed under reduced pressure and the crude product is purified by column chromatography to afford Compound D.

The Compound C products that form from the condensation of Compound B products with glucose are treated according to the above-described general procedure with 11,11-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (30); 14,14-Dideutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (23); 11,11,14,14-Tetradeutero-cis,cis,cis-octadeca-8,12,15-trienoic acid (17); and 11,11-Dideutero-cis,cis-octadeca-9,12-dienoic acid (7) as the PUFAs to afford products corresponding to the general formula of Compound D.

Example 9. ¹H- and ¹³C-NMR Analysis of Deuterated PUFAs Described in Examples 1-4 (FIG. 2)

Characteristic areas of ¹H and ¹³C spectra, all values in ppm. (Panel A) Deuteration of Lin acid at pos. 11 is confirmed by the disappearance of peaks in ¹H and ¹³C NMR spectra. Disappearance of the peak at δ_(H) 2.764 is expected due to absence of H atoms (¹H NMR). Disappearance of the peak at δ_(C) 25.5 in is due to combination of Nuclear Overhauser Effect, and splitting of this particular carbon atom into a quintet by two D atoms in the deuterated form of Lin acid. (Panel B) The ¹H NMR spectrum shows that the H atoms at C11 and C14 positions of site-specifically deuterated αLnn coincide (δ_(H) 2.801) thus deuteration at either site (11,11-H₂, 14,14-D₂ or 11,11-D₂, 14,14-H₂) leads to a 50% decrease in integration of this peak, while deuteration of both sites (11,11,14,14-D₄) leads to the complete disappearance of the peak at δ_(H) 2.801. However, ¹³C NMR experiments can clearly distinguish between the three deuterated forms, as the observed peaks for C11 and C14 positions are separated by a small but detectable difference. Thus, deuteration at either C11 or C14 positions leads to disappearance of the peak at δ_(C) 25.68 or δ_(C) 25.60, respectively, while deuteration at both sites leads to disappearance of the two corresponding peaks.

Example 10. Isotope Reinforcement can Shut Down PUFA Peroxidation

Q-less yeast (coq mutants) provide an ideal system to assess in vivo autoxidation of fatty acids. Coenzyme Q (ubiquinone or Q) serves as a small lipophilic antioxidant as well as an electron shuttle in the respiratory chain of the mitochondrial inner membrane. Ten S. cerevisiae genes (COQ1-COQ10) are required for coenzyme Q biosynthesis and function, and the deletion of any results in respiratory deficiency (Tran U C, Clarke C F. Mitochondrion 2007; 7S, 562). It was shown that the coq yeast mutants are exquisitely sensitive to autoxidation products of PUFAs (Do T Q et al, PNAS USA 1996; 93:7534-7539; Poon W W, Do T Q, Marbois B N, Clarke C F. Mol. Aspects Med. 1997; 18,s121). Although S. cerevisiae do not produce PUFAs (Paltauf F, Daum G. Meth. Enzymol. 1992; 209:514-522), they are able to utilize PUFAs when provided exogenously, allowing their content to be manipulated (Paltauf F, Daum G. Meth. Enzymol. 1992; 209:514-522). Less than 1% of Q-less (coq2, coq3, and coq5) yeast mutants is viable following a four hour treatment with linolenic acid (Do T Q et al, PNAS USA 1996; 93:7534-7539; Poon W W, Do T Q, Marbois B N, Clarke C F. Mol. Aspects Med. 1997; 18,s121). In contrast, 70% of wild-type (the parental genetic background is strain W303-1B) cells subjected to this treatment remain viable. The Q-less yeast are also hypersensitive to other PUFAs that readily autoxidize (such as arachidonic acid), but behave the same as the wild-type parental strain to treatment with the monounsaturated oleic acid (Do T Q et al, PNAS USA 1996; 93:7534-7539). The hypersensitivity of the Q-less yeast mutants is not a secondary effect of the inability to respire, because cor1 or atp2 mutant yeast (lacking either the bcl complex or the ATP synthase, respectively) show wild-type resistance to PUFA treatment (Do T Q et al, PNAS USA 1996; 93:7534-7539; Poon W W, Do T Q, Marbois B N, Clarke C F. Mol. Aspects Med. 1997; 18,s121).

A plate dilution assay can be used to assess PUFA sensitivity. This assay can be performed by spotting serial five-fold dilutions of aliquots onto YPD plate media (FIG. 3 ). The sensitivity of the different strains can be observed by visual inspection of the density of cells in each spot.

Treatment with linolenic acid causes a dramatic loss of viability of the coq null mutants. In stark contrast, coq mutants treated with the D4-linolenic acid were not killed, and retained viabilities similar to yeast treated with oleic acid. Quantitative colony counting revealed that the viability of cells treated with oleic and D4-linolenic was similar (FIG. 4 ), while the viability of the coq mutants was reduced more than 100-fold following treatment with the standard linolenic acid for 4 h. These results indicate that isotope-reinforced linolenic acid is much more resistant to autoxidation than is the standard linolenic acid, as evidenced by the resistance of the hypersensitive coq mutants to cell killing.

Example 11. GC-MS can Detect Fatty Acids and PUFAs in Yeast Cells

Yeast do not synthesize PUFAs, however they do incorporate exogenously supplied linoleic and linolenic acids (Avery S V, et al. Applied Environ. Microbiol. 1996; 62, 3960; Howlett N G, et al. Applied Environ. Microbiol. 1997; 63, 2971). Therefore, it seems likely that yeast would also incorporate exogenously supplied D4-linolenic acid. However, it is possible that the differential sensitivity to linolenic and D4-linolenic might be attributed to differences in integration into the cell rather than autoxidation. To test whether this is the case, the extent of uptake of this fatty acid was monitored. First the conditions of separation of fatty acid methyl esters (FAME) of C18:1, C18:3, D4-18:3 and C17:0 (to be used as an internal standard) were determined. The GC-MS chromatogram shown in FIG. 5 establishes both separation and sensitivity of detection of these fatty acid methyl ester standards.

Wild-type yeast were harvested during log phase growth and incubated in the presence of exogenously added fatty acid (for 0 or 4 h) in the presence of phosphate buffer plus 0.20% dextrose, as described for the fatty acid sensitivity assay. Cells were harvested, washed twice with 10 ml sterile water, and the yeast cell pellets were then processed by alkaline methanolysis as described above. The fatty acids are detected as methylesters (FAMEs) following GC-MS with C17:0 added as an internal standard (FIG. 6 ). The amounts of 18:3 and D4 detected after 4 h incubation were extrapolated from the calibration curve. These results indicate yeast avidly incorporate both linolenic and D4-linolenic acid during the 4 h incubation period. Based on these results, it is obvious that the enhanced resistance of the coq mutant yeast to treatment with D4-C18:3 is not due to lack of uptake.

D2-linolenic, 11, 11-D2-linolenic acid and 14, 14-D2-linolenic acid, were also used on this yeast model and rendered comparable protection.

Example 12. Kinetic Isotope Effect in Non-Enzymatic Oxidation of D2-LA in a Chain Reaction Format

The kinetics of oxygen consumption during the oxidation of LA and D2-LA was studied with a glass capillary microvolumeter (FIG. 7 ). The rate of oxidation, R_(OX), was measured as a slope of [O₂] traces. The rate of initiation, R_(IN), was determined by the inhibitor method with HPMC (“6-hydroxy-2,2,5,7,8-pentamethylbenzochroman”) as a reference inhibitor. R_(IN) was calculated from the induction period of inhibited oxidation, t_(IND): R_(IN)=2·[HPMC]/t_(IND). The rate of oxidation of 0.71 M LA (FIG. 7 ) was found to be 6.1×10⁻⁶ M/s. When the process was inhibited by 0.23 mM chain-breaking antioxidant HPMC, the duration of the induction period, t_(IND), was about 48 min, with the R_(IN) value of around 0.16×10⁻⁶ M/s. The length of the kinetic chain calculated from these data was: {tilde over (v)}=R_(OX)/R_(IN)=38±3. Based on this data, the calculated oxidizability of LA was 0.0215±0.008 M^(−0.5) s^(−0.5) (n=5) [Cosgrave J. P, et. al. Lipids, 1987, 22, 299-304]. For D2-LA, the reduction of R_(OX) to 0.18×10⁻⁶ M/s was observed (FIG. 7 ). In contrast to LA, addition of HPMC did not result in the decrease in R_(OX) and the appearance of any detectable induction period (data not shown). The latter precludes a direct determination of R_(IN). For a R_(IN) value for D2-LA oxidation being comparable to that of LA it follows that D2-LA oxidation was not a chain process (v=0.18×10⁻⁶/0.16×10⁻⁶≈1.1). An estimated kinetic isotope effect (“KIE”), from comparison of R_(OX) for LA and D2-LA, was around 6.1×10⁻⁶/0.18×10⁻⁶≈35. A similar KIE was determined during the oxidation of LA and 11,11-d₂-LA in Triton X-100 aqueous micelles (data not shown). For comparative purposes, the theoretical KIE is 6.9 at 25° C. See Carpenter, “Determination of Organic Reaction Mechanisms” (John Wiley & Sons, 1984), p. 89.

Example 13. Small Amounts of D2-LA Protect L A Against Peroxidation

To simulate the likely in vivo conditions, the kinetics of the oxidation of the mixtures of D2-LA and LA were studied (FIG. 8 ). In the experiments, the concentration of LA plus 11,11-d2-LA was 0.775 M; the concentration of AMVN was 0.0217 M; and the reactions were carried out at 37° C. The results afforded an R_(IN) of 1.10±0.08×10⁻⁷ M/sec. Additionally, the rate of oxidation of the mixtures was found to be non-additive and much lower than the additive value of R_(OX) for the individual compounds. Surprisingly, D2-LA essentially ‘protects’ the non-deuterated LA against autoxidation. A qualitatively similar effect was also observed during the oxidation of the mixture of 11,11-D2-LA with non-deuterated methyl linoleate (data not shown). These results suggest that even a partial replacement of non-deuterated LA by D2-LA may substantially slow down PUFA peroxidation.

Example 14. Small Amounts of D2-LA Protect L A Against Peroxidation In Vivo

The results described in Example 13 were reproduced in vivo using Q-less coq3 yeast strains and different ratios of LA to D2-LA (FIG. 9 ). Wild-type, yeast Q-less coq3, or respiratory deficient cor1 null mutants were incubated in the presence of 200 μM of LA and D2-LA at different ratios of PUFAs, as indicated in FIG. 9 . Serial dilutions (1:5) starting at 0.2 OD/ml were spotted on YPD solid plate medium. Additionally, a zero-time untreated control was utilized and the results are shown on the top left of FIG. 9 . Growth was at 30° C. The results indicate that approximately 10-15% of D2-LA was a sufficiently minimal amount to cancel the toxicity of LA. A similar incubation with the mono-deuterated PUFA, 11,11-D,H-LA, afforded no detectable loss in cell viability after 3 hours of treatment (data not shown). These results suggest that both D2-LA and 11,11-D,H-LA were resistant to lipid peroxidation.

Wild-type yeast cells were treated as described above except the yeast were treated with 200 μM of the designated fatty acid for 2 hours, washed with sterile water, and were either not treated (triangles) or treated with 50 μM CuSO₄ (squares) at room temperature. After 60 min of copper treatment cells were treated with 8 μM C11-Bodipy 581/591 for 30 min at room temperature. Four 100 μl aliquots were plated in a 96-well plate and the fluorescence was measured. Wild-type yeast cells treated with copper in the absence or presence of PUFA have significantly higher levels of lipid peroxidation as compared to yeast not treated with copper. However, copper-stressed wild-type yeast cells treated with 11,11-D₂-LA have lower levels of lipid peroxidation similar to yeast not treated with PUFA. Mono-deuterated 11,11-D,H-LA offered similar protection.

Example 15. Small Amounts of D4-ALA Protect ALA Against Peroxidation In Vivo

The experimental protocol described for Example 14 was also reproduced in vivo using Q-less coq3 yeast strains (FIG. 10 ) and different ratios of ALA to D4-ALA. Wild-type, yeast Q-less coq3, or respiratory deficient cor1 null mutants were incubated in the presence of 200 μM of ALA and D4-Lnn (Linolenic acid) at different ratios of PUFAs, as indicated in FIG. 10 . Serial dilutions (1:5) starting at 0.2 OD/ml were spotted on YPD solid plate medium. Growth was at 30° C. The results indicate that approximately 15-20% of D2-Lnn was a sufficiently minimal amount to cancel the toxicity of ALA. Moreover, results indicate that the content of PUFA taken up by yeast cells roughly reflects the ratios added and suggests that yeast cells do not discriminate among the PUFAs provided.

Example 16. D-PUFA Mitigates Oxidative Stress and Increases Survival in Retinal Cells Implicated in AMD and Diabetic Retinopathy Pathology

Several cell types, including microvascular endothelium (MVEC), retinal pigment epithelium (RPE) and retinal neurons (retinal ganglion cells) were tested for survival in cell culture. Cells were kept in the medium containing either hydrogenated (control) or deuterated D2-linoleic (ω-6; LA) and D4-linolenic (ω-3; ALA) acids (20 μM; ratio of ω-6 to ω-3: 1:1 or 2:1) for 72 hrs. The incorporation of PUFAs into cells was monitored by GC (FIG. 11 ). PUFAs were shown to be readily taken up by cells according to the Table 1, showing incorporation of PUFAs into MVECs.

TABLE 1 Area unlabelled Area labelled ratio control linoleate 78392976 4556042 0.058 linolenate 1488866 149411 0.100 PUFA linoleate 96026830 5525295 0.058 linolenate 2347729 113468 0.048 Deuterated PUFA linoleate 34957060 2599969 0.074 linolenate 747128 134824 0.180

The cells were then treated with paraquat (PQ; 500 μM), a common oxidative stress-generating compound. For survival measurement, cells were counted using haemocytometer and trypan blue exclusion method. FIG. 12 shows the survival of H- and D-PUFA treated MVEC cells after acute intoxication by paraquat. For all cell types tested, D-PUFA had protective effect compared to controls, similar to that shown in FIG. 8 for MVEC cells.

Example 17. Toxicology Studies of Mice Supplemented with D-PUFA Reveal No Anomalies in Major Blood Biomarkers

With a more protracted dosing paradigm (i.e. 3 weeks of dietary replacement), chemical analysis of blood serum of H-PUFA- and D-PUFA-supplemented mice (performed at UC Davis) revealed no difference in major biomarkers of renal function, liver function, blood lipids, etc for H-PUFA/D-PUFA saline treated mice. In this example, D-PUFA is a 2:1 mixture of D2-linoleic acid: D4-linolenic acid.

Tested parameters included measurements of triglycerides; total protein; total bilirubin; phosphorus; free fatty acids; HDL; glucose; creatine; cholesterol; calcium; blood urea nitrogen; alkaline phosphatase; albumin; aspartate aminotransferase; and others in Table 2.

TABLE 2 Alanine Mouse Sample Aminotransferase Aspartate Albumin Alkaline Blood Urea Calcium Cholesterol ID # volume U/L Aminotransferase U/L g/dl Phosphatase U/L Nitrogen mg/dl mg/dl mg/dl  4 100 273.0 3008.7 3.09 81.7 19.1 7.96 148.3  5 110 5726.7 8478.9 3.42 31.1 25.4 7.40 185.1  7 100 156.0 1470.6 2.82 35.1 18.9 7.64 151.2 10 60 518.4 4653.0 3.02 QNS 20.1 6.78 184.0 11 70 144.0 1635.3 3.63 72.7 20.3 8.75 170.8 13 14 3518.1 15669.0 QNS <0.1 31.5 QNS 166.5 14 75 216.9 2107.8 3.03 42.4 24.4 7.46 173.6 25 75 589.5 4707.0 3.20 18.8 18.0 5.97 193.4 27 100 727.2 6015.6 2.63 <0.1 36.2 5.71 166.7 28 100 468.9 4018.5 2.93 49.3 21.2 6.90 164.4 29 29 1898.1 12510.0 QNS QNS 24.9 QNS 208.8 30 100 2963.7 5371.2 3.38 50.3 18.2 6.29 174.7 Mean 76 1508 5289 3.17 52.6 22.8 7.67 168.5 D-PUFA SD 33 2225 5189 0.30 23.0 4.6 0.66 14.5 D-PUFA Mean 81 1329 6524 3.04 39.5 23.7 6.22 181.6 H-PUFA SD 31 1078 3428 0.33 17.9 8 0.51 19.0 D-PUFA Mouse Creatinine Glucose High Density Non-esterified Fatty Phosphorus Total Total Triglyceride ID # mg/dl mg/dl Lipoprotein mg/dl Acid mEq/L mg/dl Bilirubin mg/dl Protein g/dl mg/dl  4 0.189 160.2 104.49 1.08 13.07 0.185 5.32 38.9  5 0.356 355.6 134.37 1.07 18.59 0.275 6.56 57.9  7 0.154 174.6 107.39 1.11 10.14 0.192 5.26 82.7 10 0.151 136.5 138.15 1.06 QNS 0.272 6.07 46.1 11 0.179 107.9 139.86 1.18 9.33 0.162 5.72 33.5 13 1.126 176.4 135.09 0.99 QNS QNS QNS 31.5 14 0.170 93.3 47.78 1.06 10.41 0.235 6.07 43.8 25 0.126 164.5 147.96 1.01 18.39 0.269 6.74 41.0 27 1.453 88.3 98.46 0.87 24.57 0.301 6.26 26.9 28 0.232 224.9 50.54 1.02 14.16 0.231 5.87 49.6 29 0.111 QNS 77.58 0.20 QNS QNS QNS 27.9 30 0.225 227.4 131.04 1.17 21.42 0.349 6.28 46.7 Mean 0.332 172.1 115.30 1.08 12.31 0.220 5.83 47.8 D-PUFA SD 0.357 87.0 33.21 0.06 3.78 0.048 0.50 17.7 D-PUFA Mean 0.429 176.3 101.12 0.85 19.64 0.288 6.29 38 H-PUFA SD 0.575 65.5 39.40 0.38 4.44 0.050 0.36 11 D-PUFA

Example 18. Histopathologic Studies

Microscopic changes were coded by the most specific topographic and morphologic diagnosis, and the Systematized Nomenclature of Medicine (SNOMVED) and the National Toxicology Program's Toxicology Data Management System (TDMS) terminology manuals were used as guidelines. Data were recorded in Labcat® Histopathology module 4.30. A four-step grading system (minimal, mild, moderate, and marked) was used to define gradable changes.

C57BL6 male mice were dosed orally in the diet with PUFAs on Study Days 1 through 14, and were necropsied on Study Day 15. Group 1 consisted of 4 mice and received hydrogenated PUFAs. Group 2 consisted of 5 mice and received deuterated PUFAs (D2-LA and D4-ALA) On Study Day 8, all mice received intraperitoneal (IP) saline. Complete sets of protocol-specified tissues [liver (3 to 7 sections), lungs with bronchi (2 to 5 lobes), spleen, heart, and kidneys] from all submitted mice were examined histopathologically. No difference was observed between the H-PUFA and D-PUFA groups.

Example 19. Evaluation of Tissue-specific Deuteration

WT mice were housed at 12 animals (males separate from females) per cage and fed for 90 days ad libitum (typically, 5-6 g/day) on the AlN 93 diet, as pellets, with 6% total fat. Approximately 10% of that total fat was made up of 1:1 mixture of D2-LA/D4-ALA (group 1), D2-LA/ALA (group 2), or LA/ALA (control group). The animals were sacrificed, organs harvested and stored at low temperature prior to analysis without the use of preservation agents. Lipid fractions were separated, pre-treated and analyzed by LC-MS according to standard protocols using LA, D2-LA, ALA and D4-ALA as controls.

Dosage studies of 1:1 D2-LA/D4-ALA indicated that tissues became highly enriched in deuterium, with about 40% of the total fat being deuterated (FIG. 13 ). Moreover, these studies indicated that fat distribution remained relatively unchanged by the tested dosage (FIG. 14 ). After dosage studies of 1:1 D2-LA/ALA, it was determined that about 27% of the total fat was deuterated (FIG. 15 ).

Specific organs, such as the liver and brain, were also evaluated (FIGS. 16-21 ). While the liver had a different fat profile than previous tissues studied (FIG. 16 ), 90 day dosage studies with D2-LA/D4-ALA demonstrated that tissues became highly enriched in deuterium, with about 40% of the total fat being deuterated (FIG. 17 ). Moreover, the liver study indicated that fat distribution remained relatively unchanged by the tested dosage (FIG. 16-17 ). Additionally, 90 day dosage studies with D2-LA only illustrated a similar fat profile as previous studies, along with about 32% total fat being deuterated (FIG. 18 ). Consequently, fat profiles and deuteration profiles in the liver were maintained regardless of the administered deuterated component. Like the liver, the brain also had a different fat profile than previous tissues studied (FIGS. 19-21 ). 90 day dosage studies with D2-LA/D4-ALA demonstrated that tissues became highly enriched in deuterium, with about 30% of the total fat being deuterated (FIG. 19 ). Moreover, the brain study indicated that fat distribution remained relatively unchanged by the tested dosage (FIGS. 19-21 ). Additionally, 90 day dosage studies with D2-LA/ALA illustrated a similar fat profile as previous studies, along with about 23% total fat being deuterated (FIG. 20 ). Consequently, fat profiles and deuteration profiles in the brain were maintained regardless of the administered deuterated component.

Example 20: Testing Efficacy Against Non-Alcoholic Fatty Liver Disease and Steatohepatitis

Fifty male heterozygous rats, 45-days-old, from the Rattus norvegicus species and Wistar lineage are kept in polypropylene cages, in groups of five animals, under a 12 h-clear/dark cycle and under controlled temperature conditions. The induction of NASH is carried out through a diet deficient in methionine and choline (MCD) according to known procedures (See Rogers A E, Newberne P M. Alcoholic and nutritional fatty liver and cirrhosis. Am J Pathol. 1973; 73:817-20). D-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of D2-LA, D4-ALA, and 1:1 combinations of both D2-LA and D4-ALA) or H-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of LA, ALA, and 1:1 combinations of both LA and ALA) are administered daily to the rats over a three month period. During the study period, the animals are weighed on a weekly basis and the drugs dose is readjusted as necessary. On the first day of the study, besides determining the animals' weight, their blood is collected through retro-orbital plexus puncture for biochemical analysis: alanine-aminotransferase (ALT) and aspartate-aminotransferase (AST) (colorimetric test, using the Labtest kit). One day after concluding the induction period and compound administration (90 days), animals are sacrificed by decapitation. Once more, each animal's blood is collected for biochemical analysis. Then, laparotomy with total hepatectomy and liver preparation are carried out for lipoperoxidation (LPO) and histological analysis. Liver tissue samples are analyzed using the thiobarbituric-acid reactant substance (TBARS) measurement according to known methods (See Lowry et al. Protein measurement with the folin phenol reagent. J Biol Chem. 1951; 193:265-75) and the results are expressed in nmol of malondialdehyde/mg of protein. Slides with liver fragments are also dyed with hematoxilin-eosine and picrosirius, in order to evaluate the fibrosis level, and with Perls to evaluate the presence of iron stores, having been examined by an only pathologist blinded to the animals' data. The minimum histological criterion for NASH diagnosis is the presence of hepatocellular ballooning-related steatosis, involving zone 3 and lobular inflammatory infiltrate. Mallory corpuscles and sinusoidal fibrosis, involving zone 3 might be present or not. The graduation of both necroinflammatory and fibrosis activity is carried out according to known classifications (See Brunt E M, Janney C G, Di Bisceglie A M, Neuschwander-Tetri B A, Bacon B R. Nonalcoholic steatohepatitis: a proposal for grading and staging the histological lesions. Am J Gastroenterol. 1999; 94:2467-74). D2-LA and D4-ALA are expected to reduce the amount of MDA found in liver samples and reverse the histological signs of NASH.

Example 21: Testing Efficacy Against Alcoholic Fatty Liver Disease, Steatohepatitis and Cirrhosis

Fifty male heterozygous rats, 45-days-old, from the Rattus norvegicus species and Wistar lineage are kept in polypropylene cages, in groups of five animals, under a 12 h-clear/dark cycle and under controlled temperature conditions. The induction of alcoholic liver disease and cirrhosis is carried out through a diet containing 5% ethanol for 6 weeks. D-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of D2-LA, D4-ALA, and 1:1 combinations of both D2-LA and D4-ALA) or H-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of LA, ALA, and 1:1 combinations of both LA and ALA) are administered daily to the rats over a three month period. During the study period, the animals are weighed on a weekly basis and the drugs dose is readjusted as necessary. On the first day of the study, besides determining the animals' weight, their blood is collected through retro-orbital plexus puncture for biochemical analysis: alanine-aminotransferase (ALT) and aspartate-aminotransferase (AST) (colorimetric test, using the Labtest kit). One day after concluding the induction period and compound administration (90 days), the animals are sacrificed by decapitation. Once more, each animal's blood is collected for biochemical analysis. Then, laparotomy with total hepatectomy and liver preparation are carried out for lipoperoxidation (LPO) and histological analysis. Liver tissue samples are analyzed using the thiobarbituric-acid reactant substance (TBARS) measurement according to known methods (See Lowry et al. Protein measurement with the folin phenol reagent. J Biol Chem. 1951; 193:265-75) and the results are expressed in nmol of malondialdehyde/mg of protein. Slides with liver fragments are also dyed with hematoxilin-eosine and picrosirius, in order to evaluate the fibrosis level, and with Perls to evaluate the presence of iron stores, having been examined by an only pathologist blinded to the animals' data. D2-LA and D4-ALA are expected to reduce the amount of MDA found in liver samples and reverse the histological signs of fatty liver disease.

Example 22: In Vitro Model for Determining Efficacy Against Oxidative Stress in the Liver

Hepatocyte cultures can be tested for survival in cell culture in response to oxidative stress using the methodology described for Example 16. Hepatocytes are kept in a medium containing D-PUFA (0.01, 0.1, 1.0, 10.0, and 100 μM of D2-LA, D4-ALA, and 1:1 combinations of both D2-LA and D4-ALA) or H-PUFA (0.01, 0.1, 1.0, 10.0, and 100 μM of LA, ALA, and 1:1 combinations of both LA and ALA) for 72 hrs. The incorporation of PUFAs into cells is monitored by GC as described for Example 2 and 7. As described for Example 7, the hepatocytes are also treated with paraquat (PQ; 500 μM), an oxidative stress-generating compound. For survival measurement, cells are counted using haemocytometer and trypan blue exclusion method. PUFAs are expected to be readily taken up by the hepatocytes. D-PUFAs are expected to have protective effects as compared to control samples.

Example 23. Model for Testing Incorporation into Adipose and Heart Tissues

Isotope ratio Mass-spectrometry can be used to confirm incorporation of D-PUFA into the phospholipid membranes of adipose tissue and heart tissue. When delivering D2-LA and D4-ALA through dietary supplementation, incorporation into animal tissues can be monitored using an isotope ratio mass-spectrometry technique that will allow for measurement of the total increase in deuterium composition in lipid membranes, thus reporting on incorporation of D2-LA, D4-ALA, and any other PUFA derived from these compounds. Using this method, a substantial uptake of D-PUFA into animal tissue can be detected. For example, mice are supplemented with D-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of D2-LA, D4-ALA, and 1:1 combinations of both D2-LA and D4-ALA) or H-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of LA, ALA, and 1:1 combinations of both LA and ALA) as the only PUFA source for 6 days, exposed acutely to a known oxidant or saline vehicle and continued on the same diet for an additional 6 days. Adipose tissue and the heart are removed and homogenate samples from control mice and test compound-treated mice are analyzed for deuterium content as described for Example 7 above. D2-LA and D4-ALA are expected to be found in the analyzed adipose tissues and heart tissues.

Example 24. Model for Testing Efficacy Against Hypertension

The stroke-prone spontaneously hypertensive (SHRSP) rat model of hypertension, which has been previously described (McIntyre et al., 1997 Hypertension 30:1517; Alexander et al., 1999 Cardiovasc. Res. 43:798; Fennell et al., 2002 Gene Ther. 9:110), can be used for the assessment of a compound's ability to mitigate hypertension.

For example, groups (8-9 animals/group) of 8-week old male SHRSP rats are supplemented with D-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of D2-LA, D4-ALA, and 1:1 combinations of both D2-LA and D4-ALA) or H-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of LA, ALA, and 1:1 combinations of both LA and ALA) as the only PUFA source for a period of 8 weeks, and systolic blood pressure measurements are recorded at weekly intervals. Animals treated with D2-LA and D4-ALA are expected to exhibit a reduction in systolic blood pressure.

Example 25. Model for Testing Efficacy Against Various Cardiac Disorders

Test compounds disclosed herein can also be assessed using the Langendorf isolated heart perfusion model. For example, groups (8-9 animals/group) of 8-week old male rats are supplemented with D-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of D2-LA, D4-ALA, and 1:1 combinations of both D2-LA and D4-ALA) or H-PUFA (0.01, 0.1, 1.0, 10.0, and 100 mg/kg of LA, ALA, and 1:1 combinations of both LA and ALA) as the only PUFA source for a period of 8 weeks. Following the treatment period, rat hearts are analyzed by echocardiography for measurement of muscle thickness of the left ventricle, left atrium, right ventricle, and right atrium and electrocardiography for measuring electrical activity. After live evaluation, rats are humanely sacrificed and their hearts isolated and connected to the Langendorf isolated perfusion system (See Jennings et al., Am. Surg. 2004; 70(9), 797-800). Left ventricular pressure is then measured with a left ventricular balloon. Coronary flow is also measured. Cardiac function is further assessed by determining the effect of administration of test compounds on the rate of contraction and relaxation of the heart. To determine whether any observed effects on cardiac function are due to the effect of the test compound on mitochondrial function, mitochondrial activity pre-ischemia and post-ischemia is assessed for each of the treatment groups. D2-LA and D4-ALA are expected to reduce symptoms and markers associated with cardiac disorders.

CONCLUSION

While the invention has been described with reference to the specific embodiments thereof, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention. This includes embodiments which do not provide all of the benefits and features set forth herein. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, process, process step or steps, to the objective, spirit and scope of the present invention. All such modifications are intended to be within the scope of the claims appended hereto. Accordingly, the scope of the invention is defined only by reference to the appended claims. 

1. A method of treating or inhibiting the progression of a hepatic disorder, comprising: administering an effective amount of a polyunsaturated substance to a patient having alcoholic fatty liver disease, non-alcoholic fatty liver disease, steatohepatitis, cirrhosis, hepatocellular carcinoma, obstructive jaundice, cholelitiasis, or a biliary tract disease and in need of treatment, wherein the polyunsaturated substance is chemically modified such that one or more bonds is stabilized against oxidation; wherein the polyunsaturated substance or a polyunsaturated metabolite thereof comprising said one or more stabilized bonds is incorporated into the patient's body following administration. 2-30. (canceled) 